Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
VSO n abbr (BRIT) (= Voluntary Service Overseas) благотвори́тельное общество, ока́зывающее по́мощь нужда́ющимся за рубежо́м
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.