Lorenz, Bonnie A., Michael H Holroyd, and Margaret J Lewis. 1995. Nutri-Kids Visit the Zoo : Teacher Guide. : [Corvallis, Or.] : Oregon State University Extension Service ; [Pullman, Wash.] : Washington State University Cooperative Extension ; [Moscow, Idaho] : University of Idaho Cooperative Extension System ; [Washington, D.C.] : U.S. Dept. of Agriculture.