Skandapurana 4.60.96.4

4.60.96.4

caturṣvapi ca māseṣu na sāmarthyaṃ vrate yadi ..
tadorje vratinā bhāvyamapyabdaphalamicchatā .. 88 ..
avrataḥ kārtiko yeṣāṃ gato mūḍhadhiyāmiha ..
teṣāṃ puṇyasya leśopi na bhavetsūkarātmanām .. 89 ..
kṛcchraṃ vā cātikṛcchraṃ vā prājāpatyamathāpi vā ..
saṃprāpte kārtike māsi kuryācchaktyāti puṇyavān .. 4.2.60.90 ..
ekāṃtaraṃ vrataṃ kuryāttrirātra vratameva vā ..
paṃcarātraṃ saptarātraṃ saṃprāpte kārtike vratī .. 91 ..
pakṣavrataṃ vā kurvīta māsopoṣaṇameva vā ..
norjo vaṃdhyo vidhātavyo vratinā kenacitkvacit .. 92..
śākāhāraṃ payohāraṃ phalāhāramathāpi vā ..
caredyavānnāhāraṃ vā saṃprāpte kārtike vratī ..93..
nityanaimittikaṃ snānaṃ kuryādūrje vratī naraḥ ..
brahmacaryaṃ caredūrje mahāvrataphalārthavān .. 94 ..
bāhulaṃ brahmacaryeṇa yaḥ kṣipecchucimānasaḥ ..
samastaṃ hāyanaṃ tena brahmacaryakṛtaṃ bhavet ..95..
yastu kārtikikaṃ māsamupavāsaiḥ samāpayet ..
apyabdamapi teneha bhavetsamyagupoṣitam .. 96 .

And if one lacks the capacity for a vow during all four months, / then one should observe vows during Ūrja, if one desires the fruit of a whole year.
Those foolish-minded ones whose Kārtika passes without vows here, / of those swinish souls there shall not be even a speck of merit.
A Kṛcchra, or an Atikṛcchra, or even a Prājāpatya vow, / an exceedingly meritorious person should perform according to capacity when the month of Kārtika arrives.
One should perform a vow on alternate days, or a three-night vow, / a five-night or a seven-night vow, when Kārtika arrives, as a vow-keeper.
Or one should observe a fortnight's vow, or fast for the entire month; / Ūrja should never be rendered barren by any vow-keeper anywhere.
Subsisting on vegetables, subsisting on milk, or subsisting on fruit, / or subsisting on barley food, the vow-keeper should observe when Kārtika has arrived.
A man observing the vow should perform the daily and occasional ritual ablutions during Ūrja; / he should observe celibacy during Ūrja, desiring the fruit of a great vow.
He who spends the month of Kārtika in celibacy, with a pure mind, / by him the entire year has been spent practicing celibacy.
He who completes the month of Kārtika with fasts, / by him even a whole year here has been properly fasted.