SILVA, R. A.; CRESTE, J. E.; TIRITAN, C. S.; GUERRA, W. E. X.; ECKER, A. E. DO A. Nutritional diagnosis by Dris method of the cultivars coffee in the northern region of ParanĂ¡, Brazil. Coffee Science - ISSN 1984-3909, v. 10, n. 2, p. 204 - 213, 30 May 2015.