@article{IUPAC+OT07087+2019,
url = {https://doi.org/10.1351/goldbook.OT07087},
institution = {International Union of Pure and Applied Chemistry (IUPAC)},
year = {2019},
title = {open-shell systems},
doi = {doi:10.1351/goldbook.OT07087},
edition = {3.0.1}
}