H. Marschner and V. Römheld (1994): "Strategies of plants for acquisition of iron". Plant and Soil, volume 165, issue 2, pages 261–274. doi:10.1007/BF00008069
Petsch, S.T. (2014). "10.11 - The Global Oxygen Cycle". In Holland, H.D.; Turekian, K.K. (eds.). Treatise on Geochemistry. Reference Module in Earth Systems and Environmental Sciences. Vol. 10 (Second ed.). Elsevier. pp. 437–473. doi:10.1016/B978-0-08-095975-7.00811-1. ISBN978-0-08-095975-7.