Is "Vgl." (with a lower case L) or "VgI." (with an upper case i) a standard abbreviation used in footnotes and/or references/biblography of German academic publications, or is this simply an abbreviation for a name?
The paper I am reading is from 1916 or so, so whatever this is might have gone out of fashion. I am also unsure, due to the print quality, if it is a lower case L or an upper case i following Vg.
The full sentence (assuming lower case L) is:
Vgl. etwa E. Czuber, Geometrische Wahrscheinlichkeiten und Mittelwerte, Leipzig 1884, S. 197.