John L. Pollock. Henkin style completeness proofs in theories lacking negation. Notre Dame Journal of Formal Logic, 12(4):509-511, 1971. [doi]
@article{Pollock71,
title = {Henkin style completeness proofs in theories lacking negation},
author = {John L. Pollock},
year = {1971},
doi = {10.1305/ndjfl/1093894377},
url = {http://dx.doi.org/10.1305/ndjfl/1093894377},
researchr = {https://researchr.org/publication/Pollock71},
cites = {0},
citedby = {0},
journal = {Notre Dame Journal of Formal Logic},
volume = {12},
number = {4},
pages = {509-511},
}