Manava Dharmashastra 3.281

3.281

anena vidhinā śrāddhaṃ trir abdasyeha nirvapet
hemantagrīṣmavarṣāsu pāñcayajñikam anvaham //

Let him offer here below a funeral sacrifice, according to the rule given above, (at least) thrice a year, in winter, in summer, and in the rainy season, but that which is included among the five great sacrifices, every day.