Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Tom Edinburgh and Jonathan J. Day,Estimating the extent of Antarctic summer sea ice during the Heroic Age of Antarctic Exploration,The Cryosphere,1994-0424,Copernicus GmbH,2016-11-21,10,6,2721-2730,https://cir.nii.ac.jp/crid/1362262945075036672,https://doi.org/10.5194/tc-10-2721-2016