TY  - RPRT
TI  - A challenge for the future.
AU  - J VonRuden
PY  - 1968
DO  - 10.1111/j.1542-2011.1968.tb00047.x
UR  - https://pubmed.ncbi.nlm.nih.gov/5184265/
ID  - 5184265
ER  -