Differences in living things
Subtitle: an environmental investigation
By: edited and published by National Wildlife Federation ; design and illustrations by Jan Blyler.
Contributors: National Wildlife Federation.
Publisher: National Wildlife Federation
Published: 1971
Place of publication: Washington D.C
Language: eng
Notes: "One of a group of environmental units written by the EnvironmentalScience Center which is now the environmental education unit of the Minnesota environmental Sciences foundation, Inc" - inside front cover.