NA. Science Factory - LIGHT & SIGHT. S. Chand Publishing.
Chicago-čujuhus (17. p.)NA. Science Factory - LIGHT & SIGHT. S. Chand Publishing.
MLA-čujuhus (9. p.)NA. Science Factory - LIGHT & SIGHT. S. Chand Publishing.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.