TY  - BOOK
AU  - Schrankel Kenneth R. 
TI  - Study guide to accompany Ward and Hetzel's Biology: today and tomorrow 
U1  - 570 23
PY  - 1980///
CY  - St. Paul [Minn.] : 
PB  - West Publishing, 
KW  - Biology
KW  - Programmed instruction.
ER  -