Não informado. University of Pennsylvania medical bulletin. University of Pennsylvania, School of Medicine.
Chicago (17e ed.) BronvermeldingNão informado. University of Pennsylvania Medical Bulletin. Philadelphia, Pa: University of Pennsylvania, School of Medicine.
MLA (8e ed.) BronvermeldingNão informado. University of Pennsylvania Medical Bulletin. University of Pennsylvania, School of Medicine.
Let op: Deze citaties zijn niet altijd 100% accuraat.