Valmiki Ramayana Aranya Kanda Sarga 48 Shloka 6

भद्रे O noble lady, यस्य whose, तत् that, पुष्पकं नाम by name Pushpaka, कामगम् goes where one desires, शुभम् auspicious, विमानम् chariot, वीर्यादेव by valour alone, आर्जितम् gained over, येन in which, विहायसम् sky, यामि I move about.

O noble lady with my valour I gained over from Kubera the aerial chariot 'Pushpaka', which can go wherever one desires and in which I move about in the sky.