1. Reactive Nitrogen in the Environment: Too Much or Too Little of a Good Thing;UNEP and WHRC,2007
2. Nitrogen Fixation Outside and Inside Plant Tissues;Chanway,2014
3. Microorganisms in Action;Bezdicek,1998
4. The evolution and future of Earth's nitrogen cycle;Canfield;Science,2010
5. Environmental Microbiology;Pepper,2015