Carol J. Bult Harold J. Drabkin Alexei V. Evsikov Darren A. Natale Cecilia N. Arighi Natalia V. Roberts Alan Ruttenberg Peter D'Eustachio Barry Smith Judith A. Blake Cathy H. Wu The Representation of Protein Complexes in the Protein Ontology (PRO). 371 2011 12 BMC Bioinformatics http://dx.doi.org/10.1186/1471-2105-12-371 db/journals/bmcbi/bmcbi12.html#BultDENARRDSBW11