Никитинский, В.А., Пивоварова, С.В. and Шабрацкий, С.В. 2012. Not observable complex numbers in the electrical engineer and the physicist. Eastern-European Journal of Enterprise Technologies. 2, 5(50) (Jan. 2012), 46–48. DOI:https://doi.org/10.15587/1729-4061.2011.1790.