Selmke, Markus; Selmke, Sarah (2016). "Complex artificial halos for the classroom". American Journal of Physics. 84 (7). American Association of Physics Teachers: 561–564. Bibcode:2016AmJPh..84..561S. doi:10.1119/1.4953342. ISSN0002-9505.
Selmke, Markus; Selmke, Sarah (2016). "Complex artificial halos for the classroom". American Journal of Physics. 84 (7). American Association of Physics Teachers: 561–564. Bibcode:2016AmJPh..84..561S. doi:10.1119/1.4953342. ISSN0002-9505.
Selmke, Markus; Selmke, Sarah (2016). "Complex artificial halos for the classroom". American Journal of Physics. 84 (7). American Association of Physics Teachers: 561–564. Bibcode:2016AmJPh..84..561S. doi:10.1119/1.4953342. ISSN0002-9505.