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Late glacial fluctuations of the Laurentide Ice Sheet in the White Mountains of Maine and New Hampshire, U.S.A.

Published online by Cambridge University Press:  20 January 2017

Gordon R.M. Bromley ,
Brenda L. Hall ,
Woodrow B. Thompson ,
Michael R. Kaplan ,
Juan Luis Garcia  and
Joerg M. Schaefer
Gordon R.M. Bromley*
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA
Brenda L. Hall
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA
Woodrow B. Thompson
Affiliation:
Maine Geological Survey, 93 State House Station, Augusta, ME 04333-0093, USA
Michael R. Kaplan
Affiliation:
Lamont-Doherty Earth Observatory, Geochemistry, Route 9W, Palisades, NY 10964, USA
Juan Luis Garcia
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA Instituto de Geografia, Pontificia Universidad Catolica de Chile, Avenida Vicuna Mackenna 4860, Santiago 782-0436, Chile
Joerg M. Schaefer
Affiliation:
Lamont-Doherty Earth Observatory, Geochemistry, Route 9W, Palisades, NY 10964, USA
*
*Corresponding author. Fax: + 1 207 581 1203. E-mail address:[email protected] (G.R.M. Bromley).
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Abstract

Prominent moraines deposited by the Laurentide Ice Sheet in northern New England document readvances, or stillstands, of the ice margin during overall deglaciation. However, until now, the paucity of direct chronologies over much of the region has precluded meaningful assessment of the mechanisms that drove these events, or of the complex relationships between ice-sheet dynamics and climate. As a step towards addressing this problem, we present a cosmogenic 10Be surface-exposure chronology from the Androscoggin moraine complex, located in the White Mountains of western Maine and northern New Hampshire, as well as four recalculated ages from the nearby Littleton–Bethlehem moraine. Seven internally consistent 10Be ages from the Androscoggin terminal moraines indicate that advance culminated ~ 13.2 ± 0.8 ka, in close agreement with the mean age of the neighboring Littleton–Bethlehem complex. Together, these two datasets indicate stabilization or advance of the ice-sheet margin in northern New England, at ~ 14–13 ka, during the Allerød/Greenland Interstadial I.

Keywords

Laurentide Ice SheetNew EnglandDeglaciationLate glacialAllerødReadvance
Type
Original Articles
Information
Quaternary Research , Volume 83 , Issue 3 , May 2015 , pp. 522 - 530
Copyright
University of Washington

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References

Agassiz, L. (1870). On the former existence of local glaciers in the White Mountains. American Association for the Advancement of Science, Proceedings 19, 161–167.Google Scholar
Antevs, E. (1922). The recession of the last ice sheet in New England. American Geographical Society, Research Series 11, .Google Scholar
Antevs, E. (1928). The Last Glaciation With Special Reference to the Ice Sheet in North America: Research Series No. 17. American Geographical Society, .Google Scholar
Balco, G., Schaefer, J. (2006). Cosmogenic-nuclide and varve chronologies for the deglaciation of southern New England. Quaternary Geochronology 1, 15–28.CrossRefGoogle Scholar
Balco, G., Stone, J., Porter, S., Caffee, M. (2002). Cosmogenic-nuclide ages for New England coastal moraines, Martha's Vineyard and Cape Cod, Massachusetts, USA. Quaternary Science Reviews 21, 2127–2135.CrossRefGoogle Scholar
Balco, G., Stone, J., Lifton, N., Dunai, T. (2008). A complete and easily accessible means of calculating surface exposure ages or erosion rates from 10Be and 26Al measurements. Quaternary Geochronology 3, 174–195.CrossRefGoogle Scholar
Balco, G., Briner, J., Finkel, R.C., Rayburn, J.A., Ridge, J.C., Schaefer, J.M. (2009). Regional beryllium-10 production rate calibration for late-glacial northeastern North America. Quaternary Geochronology 4, 93–107.CrossRefGoogle Scholar
Bevington, P., Robinson, D. (1992). Data Reduction and Error Analysis for the Physical Sciences. WCB McGraw-Hill, New York.(320 pp.).Google Scholar
Birkel, S.D. (2010). Climate Investigations Using Ice Sheet and Mass Balance Models With Emphasis on North American Glaciation. (Ph.D. dissertation)University of Maine, Orono, Maine, USA.Google Scholar
Björck, S., Bennike, O., Rosén, P., Andresen, C.S., Bohncke, S., Kaas, E., Conley, D. (2002). Anomalously mild Younger Dryas summer conditions in southern Greenland. Geology 30, 427–430.2.0.CO;2>CrossRefGoogle Scholar
Bond, G., Broecker, W., Johnsen, S., McManus, J., Labeyrie, L., Jouzel, J., Bonani, G. (1993). Correlations between climate records from North Atlantic sediments and Greenland ice. Nature 365, 143–147.CrossRefGoogle Scholar
Borns, H.W. Jr. (1973). Late-Wisconsin fluctuations of the Laurentide Ice Sheet in southern and eastern New England. Black, R.F., Goldthwait, R., Willman, H.B. The Wisconsinan Stage Geological Society of America, Memoir. 136, 37–45.CrossRefGoogle Scholar
Borns, H.W. Jr. (1980). Glaciomarine geology of the eastern Coastal Zone, in American Quaternary Association, Field Trip A and D, Field Trip Guide: Orono. Maine, American Quaternary Association.18 pp.Google Scholar
Borns, H.W. Jr., Hughes, T.J. (1977). The implications of the Pineo Ridge readvance in Maine. Géographie Physique et Quaternaire 31, 203–206.CrossRefGoogle Scholar
Borns, H.W., Doner, L.A., Dorion, C.C., Jacobson, G.L. Jr., Kaplan, M.R., Kreutz, K.J., Lowell, T.V., Thompson, W.B., Weddle, T.K. (2004). The deglaciation of Maine, U.S.A. Ehlers, J., Gibbard, P. Quaternary Glaciations — Extent and Chronology, Volume 2, Part II Elsevier, 89–110.Google Scholar
Bowen, D.Q. (1999). Only four major 100-ka glaciations during the Brunhes Chron?. International Journal of Earth Sciences 88, 276–284.CrossRefGoogle Scholar
Briner, J.P., Davis, P.T., Miller, G.H. (2009). Latest Pleistocene and Holocene glaciation of Baffin Island, Arctic Canada: key patterns and chronologies. Quaternary Science Reviews 28, 2075–2087.CrossRefGoogle Scholar
Briner, J.P., Young, N.E., Goehring, B.M., Schaefer, J.M. (2012). Constraining Holocene 10Be production rates in Greenland. Journal of Quaternary Science 27, 2–6.CrossRefGoogle Scholar
Broccoli, A.J., Manabe, S. (1987). The influence of continental ice, atmospheric CO 2, and land albedo on the climate of the last glacial maximum. Climate Dynamics 1, 87–99.CrossRefGoogle Scholar
Broecker, W.S. (2003). Does the trigger for abrupt climate change reside in the ocean or the atmosphere?. Science 300, 1519–1522.CrossRefGoogle ScholarPubMed
Bromley, G.R.M., Putnam, A.E., Rademaker, K.M., Lowell, T.V., Schaefer, J.M., Hall, B.L., Winckler, G., Birkell, S.D., Borns, H.W. (2014). Younger Dryas deglaciation of Scotland driven by warming summers. Proceedings of the National Academy of Science 111, 6215–6219.CrossRefGoogle ScholarPubMed
Davis, R.B., Jacobson, G.L. Jr. (1985). Late glacial and early Holocene landscapes in northern New England and adjacent areas of Canada. Quaternary Research 23, 341–368.CrossRefGoogle Scholar
Denton, G.H., Hughes, T.J. (1981). The Last Great Ice Sheets. John Wiley, New York.Google Scholar
Denton, G.H., Alley, R.B., Comer, G.C., Broecker, W.S. (2005). The role of seasonality in abrupt climate change. Quaternary Science Reviews 24, 1159–1182.CrossRefGoogle Scholar
Desilets, D., Zreda, M., Prabu, T. (2006). Extended scaling factors for in situ cosmogenic nuclides: new measurements at low latitude. Earth and Planetary Science Letters 246, 265–276.CrossRefGoogle Scholar
Dieffenbacher-Krall, A.C., Nurse, A.M. (2006). Late-glacial and Holocene record of lake levels of Matthews Pond and Whitehead Lake, Northern Maine, USA. Journal of Paleolimnology 34, 283–309.CrossRefGoogle Scholar
Dorion, C.C. (1997). An Updated High Resolution Chronology of Deglaciation and Accompanying Marine Transgression in Maine. University of Maine, Orono.(M.S. thesis).Google Scholar
Dorion, C.C., Balco, G.A., Kaplan, M.R., Kreutz, K.J., Wright, J.D., Borns, H.W. Jr. (2001). Stratigraphy, paleoceanography, chronology, and environment during deglaciation of eastern Maine. Weddle, T.K., Retelle, M.J. Deglacial History and Relative Sea-level Changes, Northern New England and Adjacent Canada: Boulder, Colorado Geological Society of America Special Paper. 351, 215–242.Google Scholar
Dunai, T. (2001). Influence of secular variation of the magnetic field on production rates of in situ produced cosmogenic nuclides. Earth and Planetary Science Letters 193, 197–212.CrossRefGoogle Scholar
Dyke, A.S., Prest, V.K. (1987). Late Wisconsinan and Holocene history of the Laurentide Ice Sheet. Géographie Physique et Quaternaire 41, 237–263.CrossRefGoogle Scholar
Fenton, C.R., Hermanns, R.L., Blikra, L.H., Kubik, P.W., Bryant, C., Niedermann, S., Meixner, A., Goethals, M.M. (2011). Regional 10Be production rate calibration for the past 12 ka deduced from the radiocarbon-dated Grøtlandsura and Russenes rock avalanches at 69° N, Norway. Quaternary Geochronology 6, 437–452.CrossRefGoogle Scholar
Hall, B., Baroni, C., Denton, G., Kelly, M., Lowell, T. (2008). Relative sea-level change, Kjove Land, Scoresby Sund, East Greenland: implications for seasonality in Younger Dryas time. Quaternary Science Reviews 27, 2283–2291.CrossRefGoogle Scholar
Hostetler, S.W., Clark, P.U. (1997). Climatic controls of western U.S. glaciers at the last glacial maximum. Quaternary Science Reviews 16, 505–511.CrossRefGoogle Scholar
Hulbe, C.L., MacAyeal, D.R., Denton, G.H., Kleman, J., Lowell, T.V. (2004). Catastrophic ice shelf breakup as the source of Heinrich event icebergs. Paleoceanography 19, 10.1029/2003PA000890.CrossRefGoogle Scholar
Kaplan, M.R. (1999). Retreat of a tidewater margin of the Laurentide ice sheet in eastern coastal Maine ca. 14 to 13,000 14C yrs BP. Geological Society of America Bulletin 111, 620–633.2.3.CO;2>CrossRefGoogle Scholar
Kaplan, M.R. (2007). Major ice sheet response in eastern New England to a cold North Atlantic region, ca. 16–15 cal ka BP. Quaternary Research 68, 280–283.CrossRefGoogle Scholar
Kelly, M.A., Lowell, T.V., Hall, B.L., Finkel, R.C., Schaefer, J.M., Goehring, B.M., Alley, R.B., Denton, G.H. (2008). A 10Be chronology of late-glacial and Holocene mountain glaciation in the Scoresby Sund region, east Greenland: implications for seasonality during late-glacial time. Quaternary Science Reviews 27, 2273–2282.CrossRefGoogle Scholar
Kelly, M.A., Lowell, T.V., Applegate, P.J., Phillips, F.M., Schaefer, J.M., Smith, C.A., Kim, H., Leonard, K.C., Hudson, A.M. (2013). A locally calibrated, late glacial 10Be production rate from a low-latitude, high-altitude site in the Peruvian Andes. Quaternary Geochronology 10.1016/j.quageo.2013.10.007.Google Scholar
Koteff, C., Pessl, F. (1981). Systematic ice retreat in New England. United States Geological Survey Professional Paper 1179, (20 pp.).Google Scholar
Lal, D. (1991). Cosmic ray labeling of erosion surfaces: in situ nuclide production rates and erosion models. Earth and Planetary Science Letters 104, 424–439.CrossRefGoogle Scholar
Lamothe, M. (1992). Pleistocene stratigraphy and till geochemistry of the Miramichi Zone, New Brunswick. Geological Survey of Canada, Bulletin 433, .Google Scholar
Lifton, N., Bieber, J., Clem, J., Duldig, M., Evenson, P., Humble, J., Pyle, R. (2005). Addressing solar modulation and long-term uncertainties in scaling secondary cosmic rays for in situ cosmogenic nuclide applications. Earth and Planetary Science Letters 239, 140–161.CrossRefGoogle Scholar
Lohne, O.S., Bondevik, S., Mangerud, J., Svendsen, J.I. (2007). Sea-level fluctuations imply that the Younger Dryas ice-sheet expansion in western Norway commenced during the Allerød. Quaternary Science Reviews 26, 2128–2151.CrossRefGoogle Scholar
Lowe, J.J., Rasmussen, S.O., Björck, S., Hoek, W.Z., Steffensen, J.P., Walker, M.J.C., Yu, Z.C., the INTIMATE group, (2008). Synchronisation of palaeoenvironmental events in the North Atlantic region during the Last Termination: a revised protocol recommended by the INTIMATE group. Quaternary Science Reviews 27, 6–17.CrossRefGoogle Scholar
Lowell, T.V., Hayward, R.K., Denton, G.H. (1999). Role of climate oscillations in determining ice-margin position: hypothesis, examples, and implications. Mickelson, D.M., Attig, J.W. Glacial Processes Past and Present: Geological Society of America Special Paper 337 Geological Society of America, Boulder, CO.193–203.Google Scholar
Lyell, C. (1850). A Second Visit to the United States of North America. 2nd ed.John Murray, London.Google Scholar
MacAyeal, D.R. (1993). Binge/purge oscillations of the Laurentide Ice Sheet as a cause of the North Atlantic's Heinrich events. Paleoceanography 8, 775–784.CrossRefGoogle Scholar
Mangerud, J., Landvik, J.Y. (2007). Younger Dryas cirque glaciers in western Spitsbergen: smaller than during the Little Ice Age. Boreas 36, 278–285.CrossRefGoogle Scholar
Nishiizumi, K., Imamura, M., Caffee, M.W., Southon, J.R., Finkel, R.C., McAninch, J. (2007). Absolute calibration of 10Be AMS standards. Nuclear Instruments and Methods in Physics Research B 258, 403–413.CrossRefGoogle Scholar
Oldale, R.N. (1982). Pleistocene stratigraphy of Nantucket, Martha's Vineyard, the Elizabeth Islands, and Cape Cod, Massachusetts. Larson, G.J., Stone, B.D. Late Wisconsinan Glaciation of New England: Proceedings of the Symposium Kendall/Hunt, Dubuque, IA.1–34.Google Scholar
Oldale, R.N., O'Hara, C.J. (1984). Glaciotectonic origin of the Massachusetts coastal end moraines and a fluctuating late Wisconsinan ice margin. GSA Bulletin 95, 61–74.2.0.CO;2>CrossRefGoogle Scholar
Oviatte, C.G. (1997). Lake Bonneville fluctuations and global climate change. Geology 25, 155–158.2.3.CO;2>CrossRefGoogle Scholar
Parent, M., Occhietti, S. (1988). Late Wisconsinan deglaciation and Champlain Sea invasion in the St. Lawrence Valley, Québec. Géographie Physique et Quaternaire 42, 215–246.CrossRefGoogle Scholar
Peteet, D.M., Beh, M., Orr, C., Kurdyla, D., Nichols, J., Guilderson, T. (2012). Delayed deglaciation or extreme Arctic conditions 21–16 ca. ka at southeastern Laurentide Ice Sheet margin?. Geophysical Research Letters 39, L11706 10.1029/2012GL051884.CrossRefGoogle Scholar
Pratt, R.M., Schlee, J. (1969). Glaciation on the continental margin off New England. Geological Society of America Bulletin 80, 2335–2342.CrossRefGoogle Scholar
Putnam, A.E., Putnam, D.E. (2009). Inactive and relict rock glaciers of the Deboullie Lakes Ecological Reserve, northern Maine, USA. Journal of Quaternary Science 24, 773–784.CrossRefGoogle Scholar
Putnam, A.E., Schaefer, J.M., Barrell, D.J.A., Vandergoes, M., Denton, G.H., Kaplan, M.J., Finkel, R.C., Schwartz, R., Goehring, B.M., Kelley, S.M. (2010). In situ cosmogenic 10Be production-rate calibration from the Southern Alps, New Zealand. Quaternary Geochronology 5, 392–409.CrossRefGoogle Scholar
Rampton, N., Gauthier, R.C., Thibault, J., Seaman, A.A. (1984). Quaternary geology of New Brunswick. Memoirs. Geological Survey of Canada 416, .Google Scholar
Richard, P.J.H., Occhietti, S. (2005). 14C chronology for ice retreat and inception of Champlain Sea in the St. Lawrence Lowlands, Canada. Quaternary Research 63, 353–358.CrossRefGoogle Scholar
Ridge, J. (2004). The Quaternary glaciation of western New England with correlations to surrounding areas. Ehlers, J., Gibbard, P. Quaternary Glaciations — Extent and Chronology Elsevier, 169–199.CrossRefGoogle Scholar
Ridge, J., Larsen, F. (1990). Reevaluation of Antevs' New England varve chronology and new radiocarbon dates of sediments from glacial Lake Hitchcock. Geological Society of America Bulletin 102, 889–899.2.3.CO;2>CrossRefGoogle Scholar
Ridge, J., Thompson, W., Brochu, M., Brown, S., Fowler, B. (1996). Glacial geology of the upper Connecticut Valley in the vicinity of the lower Ammonoosuc and Passumpsic Valleys of New Hampshire and Vermont. Van Baalen, M. Guidebook to Field Trips in Northern New Hampshire and Adjacent Regions of Maine and Vermont: New England Intercollegiate Geologic Conference, 88th Annual Meeting 309–340.Google Scholar
Ridge, J.C., Bensonen, M.R., Brochu, M., Brown, S.L., Callahan, J.W., Cook, G.J., Nicholson, R.S., Toll, N.J. (1999). Varve, palaeomagnetic and 14C chronologies for Late Pleistocene events in New Hampshire and Vermont. Thompson, W.B., Fowler, B.K., Davis, T. Late Quaternary History of the White Mountains, New Hampshire and Adjacent South-eastern Québec Géographie physique et Quaternaire.53, 79–106.Google Scholar
Ridge, J., Canwell, B., Kelly, M., Kelley, S. (2001). Atmospheric 14C chronology for late Wisconsinan deglaciation and sea-level change in eastern New England using varve and paleomagnetic records. Weddle, T., Retelle, M. Deglacial History and Relative Sea-level Changes, Northern New England and Adjacent Canada Geological Society of America Special Paper.351, 173–191.Google Scholar
Rodrigues, C.G. (1992). Successions of invertebrate microfossils and the late Quaternary deglaciation of the central St. Lawrence Lowland, Canada and United States. Quaternary Science Reviews 11, 503–534.CrossRefGoogle Scholar
Schaefer, J.M., Denton, G.H., Kaplan, M., Putnam, A., Finkel, R.C., Barrell, D.J.A., Andersen, B.G., Schwartz, R., Mackintosh, A., Chinn, T., Schlucter, C. (2009). High-frequency Holocene glacier fluctuations in New Zealand differ from the northern signature. Science 324, 622–625.CrossRefGoogle ScholarPubMed
Smith, G.W., Hunter, L.E. (1989). Deglaciation of coastal Maine. Tucker, R.D., Marvinney, R.G. (Eds.), Studies in Maine Geology. Quaternary geology: Augusta Maine Geological Survey 6, 13–32.Google Scholar
Stone, G.H. (1880). Note on the Androscoggin glacier. American Naturalist 14, 299–302.Google Scholar
Stone, J.O.H. (2000). Air pressure and cosmogenic isotope production. Journal of Geophysical Research 105, 23753–23759.CrossRefGoogle Scholar
Stone, B.D., Borns, H.W. (1986). Pleistocene glacial and interglacial stratigraphy of New England, Long Island, and adjacent Georges Bank and Gulf of Maine. Sibrava, V., Bowen, D.Q., Richmond, G.M. Quaternary Glaciations in the Northern Hemisphere Pergamon Press, Oxford.39–52.Google Scholar
Stone, J.R., DiGiacomo-Cohen, M., Lewis, R.S., Goldsmith, R. (1998). Recessional moraines and the associated deglacial record of southeastern Connecticut and Long Island Sound. Murray, D.P. Guidebook to Field Trips in Rhode Island and Adjacent Regions of Connecticut and Massachusetts: New England Intercollegiate Geologic Conference, 90th Annual Meeting, Kingston, Rhode Island.B7-1-B7-20.Google Scholar
Thompson, W.B. (1999). History of research on glaciation in the White Mountains, New Hampshire (U.S.A.). Géographie Physique et Quaternaire 53, 7–24.CrossRefGoogle Scholar
Thompson, W. B., BornsH, W. Jr.. (1985). Surficial geologic map of Maine. Maine Geological Survey. 1:500,000-scale map.Google Scholar
Thompson, W.B., Fowler, B.K. (1989). Deglaciation of the upper Androscoggin River valley and northeastern White Mountains, Maine and New Hampshire. Tucker, R.D., Marvinney, R.G. Studies in Maine Geology–Volume 6: Quaternary Geology Maine Geological Survey, Augusta.Google Scholar
Thompson, W.B., Fowler, B.K., Flanagan, S.M., Dorion, C.C. (1996). Recession of the Late Wisconsinan ice sheet from the northwestern White Mountains, New Hampshire. Van Baalen, M.R. Guidebook to Field Trips in Northern New Hampshire and Adjacent Regions of Maine and Vermont Harvard University Department of Earth & Planetary Sciences, Cambridge, Mass.Google Scholar
Thompson, W.B., Fowler, B.K., Dorion, C.C. (1999). Deglaciation of the northwestern White Mountains, New Hampshire. Géographie Physique et Quaternaire 53, 59–77.CrossRefGoogle Scholar
Thompson, W., Hildreth, C., Boisvert, R., Dorion, C., Fowler, B. (2002). Glacial geology and archaeology of the northern White Mountains, New Hampshire. Guidebook for the 65th Annual Reunion of the Northeastern Friends of the Pleistocene .Google Scholar
Thompson, W.B., Borns, H.W. Jr., Hall, B. (2007). Extrapolation of the Littleton–Bethlehem (Older Dryas) and Pineo Ridge moraine systems across New Hampshire and Maine. Geological Society of America Abstracts with Programs 39, 55.Google Scholar
Thompson, W.B., Griggs, C.B., Miller, N.G., Nelson, R.E., Weddle, T.K., Kilian, T.M. (2011). Associated terrestrial and marine fossils in the late-glacial Presumpscot Formation, southern Maine, USA, and the marine reservoir effect on radiocarbon ages. Quaternary Research 75, 552–565.CrossRefGoogle Scholar
Tucholke, B.E., Hollister, C.D. (1973). Late Wisconsin glaciation of the southwestern Gulf of Maine: new evidence from the marine environment. GSA Bulletin 84, 3279–3296.2.0.CO;2>CrossRefGoogle Scholar
Upham, W. (1904). Moraines and eskers of the last glaciation in the White Mountains. The American Geologist 33, 7–14.Google Scholar
Williams, J., Barry, R.G., Washington, W.M. (1974). Simulation of the atmospheric circulation using the NCAR Global Circulation Model with ice age boundary conditions. Journal of Applied Meteorology 13, 305–317.2.0.CO;2>CrossRefGoogle Scholar
Wolfe, A.P. (1996). A high-resolution late-glacial and early Holocene diatom record from Baffin Island, eastern Canadian Arctic. Canadian Journal of Earth Sciences 33, 928–937.CrossRefGoogle Scholar
Young, N.E., Schaefer, J.M., Briner, J.P., Goehring, B.M. (2013). A 10Be production-rate calibration for the Arctic. Journal of Quaternary Science 28, 515–526.CrossRefGoogle Scholar