Skandapurana 5.57.41

5.57.41

tathā śivasya cāṣṭamyāṃ caitraśukle viśeṣataḥ ..
caturdaśyāṃ mahābhāga tava snehānna saṃśayaḥ .. 41 ..

and of Śiva on the eighth day, especially during the bright fortnight of Caitra; / [and] on the fourteenth day, O fortunate one, out of love for you, without a doubt;