ETTALA, T.; KREULA, M.; TÄHTINEN, H. The effect of sulphur deficiency and sulphur fertilisation on the nitrogen compounds of timothy . Agricultural and Food Science, [S. l.], v. 50, n. 2, p. 137–146, 1978. DOI: 10.23986/afsci.71966. Disponível em: https://journal.fi/afs/article/view/71966. Acesso em: 24 jul. 2024.