Skandapurana 5.29.140

5.29.140

śaivāḥ pāśupatāścaiva tathā kāpālikāśca ye ..
mahāvratadharāścānye śivabhaktiparāyaṇāḥ .. 6.29.140 ..

Śaivas, Pāśupatas, and also Kāpālikas, / and others observing the great vows, devoted to the worship of Śiva;