From Open Babel
@Article{ml91,
author = {E. C. Meng and R. A. Lewis},
title = {{D}etermination of {M}olecular {T}opology and {A}tomic {H}ybridisation
{S}tates from {H}eavy {A}tom {C}oordinates},
journal = {J. Comp. Chem.},
year = {1991},
volume = {12},
pages = {891-898},
}