Plasma concentrations of beta-endorphin in smokers who consume different numbers of cigarettes per day

1. Del Arbol, J.L.
2. Raya Muñoz, J.
3. Ojeda, L.
4. López Cascales, A.
5. Rico Irles, J.
6. Miranda, M.T.
7. Ruiz Requena, M.E.
8. Aguirre, J.C.