TY  - RPRT
TI  - What is it?
AU  - D S Durham
AU  - L S Ibels
PY  - 1980
DO  - 10.1016/s0140-6736(80)90163-4
UR  - https://pubmed.ncbi.nlm.nih.gov/6105435/
ID  - 6105435
ER  -