Skandapurana 1.4.59.121

1.4.59.121

oṃgaṇapatimaṃtrasya gaṇako nāma ṛṣiḥ vighneśvaro devatā gaṃ bījam oṃśaktiḥ pūjārthe japārthe vā tilakārthe vā manasa īpsitārthe homārthe vā viniyoga iti ..

Of the Oṃ-Gaṇapati mantra, the seer is Gaṇaka; the deity is Vighneśvara; the seed-syllable is gaṃ; the energy is oṃ; the application is for worship, for recitation, for applying the forehead mark, for the heart's desired purpose, or for the fire oblation."