TY  - BOOK
AU  - Ereshefsky,Marc
TI  - The Units of evolution: essays on the nature of species 
SN  - 0262550202 (pbk.)
AV  - QH380 .U54 1992
U1  - 574/.012 20
PY  - 1992///
CY  - Cambridge, Mass.
PB  - MIT Press
KW  - Species
N1  - "A Bradford book."; Includes bibliographical references and index
ER  -