TY  - RPRT
TI  - Countable entities: developmental changes.
AU  - E F Shipley
AU  - B Shepperson
PY  - 1990
DO  - 10.1016/0010-0277(90)90041-h
UR  - https://pubmed.ncbi.nlm.nih.gov/2311354/
ID  - 2311354
ER  -