Goatley, James L.; Lewis, Ralph W. «Composition of Guttation Fluid from Rye, Wheat, and Barley Seedlings». Plant Physiology, 41, 3, 3-1966, pàg. 373–375. DOI: 10.1104/pp.41.3.373. PMC: 1086351. PMID: 16656266.
Goatley, James L.; Lewis, Ralph W. «Composition of Guttation Fluid from Rye, Wheat, and Barley Seedlings». Plant Physiology, 41, 3, 3-1966, pàg. 373–375. DOI: 10.1104/pp.41.3.373. PMC: 1086351. PMID: 16656266.