Belevitch, V, "Summary of the history of circuit theory", Proceedings of the IRE, vol 50, Iss 5, pp.848-855, May 1962 DOI:10.1109/JRPROC.1962.288301Je zde použita šablona {{DOI}} označená jako k „pouze dočasnému použití“..
worldcat.org
Alexander Russell, A Treatise on the Theory of Alternating Currents, volume 1, chapter XXI, Cambridge: University Press 1904 OCLC264936988.
