TY  - RPRT
TI  - Birth order and PPS affiliation.
AU  - L K Waters
AU  - W E Kirk
PY  - 1967
DO  - 10.1080/00223980.1967.10544923
UR  - https://pubmed.ncbi.nlm.nih.gov/6056826/
ID  - 6056826
ER  -