>There are 24 upavyūhas of Viṣṇu in the Pāñcarātra tradition,
>distinguished by the order in which their four hands display the discus,
>conch, club and lotus flower. (I regret that I have no textual source
>for this -- perhaps someone else does?)
--------Martin Gansten
mentions
Padma Samhita (Jnana kanda: 2, 26- 28)
as the source for Chaturvimshati murti.
The blogger gives a very detailed analysis of the topic.
interestingly there is a table connecting the 24 upavyuhas to 24 letters of the Gayatri Mantra.
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