K.C., P. Theory of Shadow. Himalayan Physics, [S. l.], v. 1, p. 101–105, 2011. DOI: 10.3126/hj.v1i0.5194. Disponível em: https://www.nepjol.info/index.php/HP/article/view/5194. Acesso em: 28 mar. 2024.