TY  - RPRT
TI  - Opiate self-administration.
AU  - Zheng-Xiong Xi
AU  - Elliot A Stein
PY  - 2003
DO  - 10.1385/1-59259-379-8:251
UR  - https://pubmed.ncbi.nlm.nih.gov/12703330/
ID  - 12703330
ER  -