Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 6 · Calendar, Muhurta Elements
कालमानं मुहूर्ताङ्गानि च
द्वादश्यूर्जे शुक्लपक्षे नवम्यच्छेश्वयुज्यपि ।चैत्रे भाद्रपदे चैव तृतीया शुक्लसंज्ञिता ॥ १४९ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 149.
The 12th of the bright fortnight in Urja, and the 9th in Ashvayuji also. In Chaitra and in Bhadrapada, the 3rd of the bright fortnight is called Shukla.
Simple meaning: More holy days: bright 12th in Urja and bright 9th in Ashvina. The bright 3rd of Chaitra and Bhadrapada is called Shukla.
एकादशी सिता पौषे ह्याषाढेर्देशमीसिता ।
More holy days: the bright 11th of Pausha, the 10th of Ashadha, the 7th of Magha and the dark 8th of Nabhasya.
श्रावणे मास्यमावास्या फाल्गुने मासि पौर्णिमा ।
More holy days: new moon of Shravana, and full moons of Phalguna, Ashadha, Kartika, Jyeshtha and Chaitra.
मन्वादयो मानवानां श्राद्धेष्वत्यंतपुण्यदा ।
These fourteen days are very good for ancestor rites. A dark 13th in Bhadrapada with Moon in Magha is special.