Usha P. (2012). Poonthananthinte bhakthiyum tathwachinthayum. Vallathol Vidyapeetham.
Dyfyniad Arddull ChicagoUsha P. Poonthananthinte Bhakthiyum Tathwachinthayum. Sukapuram: Vallathol Vidyapeetham, 2012.
Dyfyniad MLAUsha P. Poonthananthinte Bhakthiyum Tathwachinthayum. Vallathol Vidyapeetham, 2012.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.