APA (7th ed.) Citation

Ettala, T., Kreula, M., & Tähtinen, H. (1978). The effect of sulphur deficiency and sulphur fertilisation on the nitrogen compounds of timothy. Agricultural and Food Science, 50(2), 137.

Chicago Style (17th ed.) Citation

Ettala, Terttu, Matti Kreula, and Hilkka Tähtinen. "The Effect of Sulphur Deficiency and Sulphur Fertilisation on the Nitrogen Compounds of Timothy." Agricultural and Food Science 50, no. 2 (1978): 137.

MLA (9th ed.) Citation

Ettala, Terttu, et al. "The Effect of Sulphur Deficiency and Sulphur Fertilisation on the Nitrogen Compounds of Timothy." Agricultural and Food Science, vol. 50, no. 2, 1978, p. 137.