López, G., and M. Avila. “Effects on the Quantum Not and Controlled-Not Gates of a Modular Magnetic Field in the Z-Direction in a Chain of Nuclear Spin System”. Revista Mexicana De Física, vol. 57, no. 3, Jan. 2011, pp. 215-0, https://rmf.smf.mx/ojs/index.php/rmf/article/view/3828.