(JA) Akama K, Kameyama S, Ito A, Murata R, [In vitro test of toxinogenicity of Corynebacterium diphtheriae (Elek's method)], in Nippon Saikingaku Zasshi, vol. 21, n. 9, settembre 1966, pp. 557–63, PMID4962656.
Ouchterlony O, In vitro method for testing the toxin-producing capacity of diphtheria bacteria, in Acta Pathol Microbiol Scand, vol. 25, n. 1-2, 1948, pp. 186–91, PMID18887479.