@inproceedings{holtedahl1967a,
title={A proof of the existence of minimal$R$-algebra resolutions},
author={Holtedahl Tor Gulliksen},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203214062588050},
booktitle={Acta Mathematica},
volume={120},
number={1},
pages={53-58},
year={1967},
}
Holtedahl Tor Gulliksen. A proof of the existence of minimal$R$-algebra resolutions. 1967. Vol. 120. In Acta Mathematica. pp.53-58. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203214062588050.