Balakrishanan V V, . (1980). Chetikalum Avayute Oushadhagunangalum. : .
Balakrishanan V V, . 1980. Chetikalum Avayute Oushadhagunangalum. : .
Balakrishanan V V, . Chetikalum Avayute Oushadhagunangalum. : . 1980.