↑(en) Andrzej Jaworski, JÓzef S. Kwiatkowski et Bogdan Lesyng, « Why isoguanine and isocytosine are not the components of the genetic code », International Journal of Quantum Chemistry, vol. 28, no S12, , p. 209-216 (DOI10.1002/qua.560280720, lire en ligne)
↑(en) Christopher Roberts, Rajanikanth Bandaru et Christopher Switzer, « Theoretical and Experimental Study of Isoguanine and Isocytosine: Base Pairing in an Expanded Genetic System », Journal of the American Chemical Society, vol. 119, no 20, , p. 4640-4649 (DOI10.1021/ja970123s, lire en ligne)