@article{Leen1988,
author = { Leen, T.M. and Graff, M.M. } ,
title = "{Oxygen chemistry of shocked interstellar clouds. III - Sulfur and oxygen species in dense clouds}" ,
journal = {Astrophysical Journal} ,
year = 1988 ,
volume = 325 ,
pages = {411-416} ,
doi = {10.1086/166013}
}