References

RArṇ, 14, 20.2
  tasya mantraṃ pravakṣyāmi tridaśairapi durlabham //Context
RArṇ, 14, 123.2
  eṣa siddharasaḥ sākṣāt durlabhastridaśairapi //Context
RArṇ, 15, 6.3
  punaranyaṃ pravakṣyāmi prayogaṃ bhuvi durlabham //Context
RArṇ, 16, 82.2
  vedhayedaṣṭalohāni devānāmapi durlabham //Context