John Thomas Bealby, 1911 Encyclopædia Britannica, Volume 16… (1911)
“ At the same time he advanced reasons for believing that Przhevalsky’s lake-basins, the southern Lop-nor, are of quite recent origin—indeed, he fixed upon 1720 as the probably approximate date of their formation, a date which von Richthofen would alter to 1750. Besides this, Sven Hedin argued that there exists a close inter-relation between the northern Lop-nor lakes and the southern Lop-nor lakes, so that as the water in the one group increases, it decreases to the same proportion and volume in the other. ”
