TY  - RPRT
TI  - Interlocking and collision in multiple pregnancies; two case reports.
AU  - R O SWANN
PY  - 1957
DO  - 10.1016/0002-9378(57)90406-4
UR  - https://pubmed.ncbi.nlm.nih.gov/13411061/
ID  - 13411061
ER  -