Quality control of food products purchased by the National School-Feeding Programme in Pernambuco, Northeast Brazil, from 1985 to 1988

N.B. Guerra, E.M.F. Pires, G. de C. Martins, J.B. Lima Filho, G.N.B. Guerra, L.B. Borges, M.O.C. Tavares, M.L.Cavalcante, A.B. de Melo Filho, A.R. de Oliveira, M.M. Becerra, S.C. de Melo Filho, V.A. Silva