Dieter Koschel, Peter Merlet e Claudia Heinrich-Sterzel, N Nitrogen, collana Gmelin Handbook of Inorganic and Organometallic Chemistry - 8th Edition Ser, 8ªed., Springer Berlin / Heidelberg, 1993, p.167, ISBN978-3-662-06336-1. URL consultato l'8 dicembre 2025.