Rules for Sraddha - Verse 40-41

There are yet other sacred times proper to the Sraddha ceremonies. They are—the third day of the month Vaisakha, the ninth day of the bright fortnight in die month Karttika, the thirteenth day of the dark fortnight in the month Bhadra pada, the fifteenth day of the month Magha, the eclipses of the sun and the moon and all the four Astakas (the eighth day of each quarter of the year) and at the commencement of the two \yanas or solstices (Utiarayana and Daksinayana).