J. Kannan
"Gaussian integer solutions to space Pythagorean Equation X2+Y2+Z2=W2".
International Journal of Modern Trends in Engineering and Research,
vol: 3,
No. 4
Apr. 2016, pp: 287 - 289,
https://scholar9.com/publication-detail/gaussian-integer-solutions-to-space-pythagorean-eq-26684
