Statistical evaluation of the persistence of acquired hypersensitivity by standardized patch tests - Ayala, F; Balato, N; Lembo, G; Patruno, C; Fabbrocini, G; Nofroni, I; Magliocchetti, N; Schena, D; Rafanelli, A; Seidenari, S; Motolese, A; Angelini, G; Tosti, A; Saccabusi, S; Pigatto, P; Lisi, P (Contact Dermatitis, 1996)