Citation: Hw. Shu et al., THE EFFECTS OF PROTECTION BY D-PEN(2)-D-PEN(5)-ENKEPHALIN OR D-ALA(2)-NMEPHE(4)-GLY-OL-ENKEPHALIN AGAINST BETA-CHLORNALTREXAMINE IN THE SPINAL GORD ON THE ANTINOCICEPTION INDUCED BY BETA-ENDORPHIN ADMINISTEREDINTRACEREBROVENTRICULARLY IN THE MOUSE, Neuropeptides, 27(2), 1994, pp. 143-149