00447nam a2200145Ia 4500003000900000008004100009040001600050080001700066100002800083245006900111260004400180300001500224650004100239700002100280IN-BaIIA211028s9999    xx            000 0 eng d  cIIA Library  a621.383bCAM  aCampbell, Robert Norman 0aPhotoelectric cellscNorman Robert Campbell and Dorothy Ritchie.  aLondonbSir Isaac Pitman and Sonsc1929  avii, 209p.  aAstronomy and Astrophysics Thesaurus  aRitchie, Dorothy