Sangoi, L. and Kruse, N.D. 1994. Different amounts of nitrogen, phosphorus and potash and agronomic traits of potato on two pH levels. Pesquisa Agropecuaria Brasileira. 29, 9 (Sep. 1994), 1333–1343. DOI:https://doi.org/10.1590/S1678-3921.pab1994.v29.4182.