Skandapurana 16.234.5

16.234.5

athocustridaśāḥ sarve suprītā bharataṃ nṛpam ..
tuṣṭāstava mahābāho yajñaiḥ saṃtarpitā vayam ..
varaṃ vṛṇīṣva rājeṃdra yatte manasi varttate .. 4. ..
.. rājovāca .. ..
atrāgatya naro bhaktyā yaḥ snānaṃ kurute naraḥ ..
daśānāmaśvamedhānāṃ sa prāpnotu phalaṃ śubham ... 5 ..

Then all the gods, well-pleased, said to King Bharata: / "O mighty-armed one, we are pleased with you, fully gratified by your sacrifices; / choose a boon, O king of kings, whatever is in your mind." / The king said: / "Whatever man comes here and performs a ritual ablution with devotion, / let that man obtain the auspicious fruit of ten horse sacrifices."