Yerukala references in Google Books
• Castes And Tribes Of Southern India By Edgar Thurston, K. Rangachari.
• People of India By Kumar Suresh Singh, B. V. Bhanu, Anthropological Survey of India.
• The Madras journal of literature and science By Madras literary society.
• Encyclopaedia of Indian Tribes By Shyam Singh Shashi
• Miscellaneous Essays Relating to Indian Subjects By Brian Houghton Hodgson.
• The Cyclopaedia of India and of Eastern and Southern Asia By Edward Balfour.
• The Cyclopaedia of India and of Eastern and Southern Asia By Edward Balfour.
• A Sketch of the Modern Languages of the East Indies By Robert Needham Cust.
• Ethnographic Notes in Southern India By Edgar Thurston
• Dishonoured by History: "criminal Tribes" and British Colonial Policy By Meena Radhakrishna.
• Manual of the Administration of the Madras Presidency By Madras (Presidency).
• The Castes and Tribes of H.E.H. the Nizam's Dominions By Syed Siraj ul Hassan.