To cite the service as such, we suggest the following BibTeX entry:
@MISC{vo:_cs_srv, year=2007, title={Published Services}, author={{PDS}-{PPI}}, url={http://vo-pds-ppi.igpp.ucla.edu/__system__/services/overview/info}, howpublished={{VO} resource provided by the {PDS}-{PPI} VO server} }