Biodiversity Heritage Library
By "Groos, Karl, 1861-"
The play of animals, by Karl Groos. Tr. with the author's cooperation by Elizabeth L. Baldwin; with a preface and an appendix by J. Mark Baldwin.
By: Groos, Karl, - Baldwin, Elizabeth L. - Baldwin, James Mark,
Publication info: New York,D. Appleton
Contributed by: NCSU Libraries (archive.org)