1. Forrester, A.R., Hay, J.M., Thomson, R.H.: Organic Chemistry of Stable Free Radicals, p. 111–136; New York, N.Y.: Academic Press 1968. (Diarylamino Radicals).
2. Forrester, A.R., Hay, J.M., Thomson, R.H.: Organic Chemistry of Stable Free Radicals, p. 137–179; New York, N.Y.: Academic Press 1968. (Hydrazyls).
3. Braun, D., Peschk, G., Hechler, E.: Chemiker Ztg., 94 (1970) 703. (Über Struktur und Stabilität aromatischer Hydrazyle).
4. Scheffler, K., Stegmann, H.B.: Elektronenspinresonanz, p. 317–321, 329–338, 367–372. Berlin, Heidelberg, New York: Springer 1970. (Pikrylhydrazyle, Oximino-Radikale, Aminyle, Verdazyle, Phenoxazinyle, Phenothiazinyle).
5. Beinert, H.: Biol. Appl. Electron Spin Resonance, p. 351–410. Editor H.M. Swartz; New York, N.Y.: Wiley 1972. (Flavines and flavoproteins, including iron-sulfur proteins).