Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 20
Sanskrit:
देवासुरे युधि च दैत्यपतीन् सुरार्थेहत्वान्तरेषु भुवनान्यदधात् कलाभि: ।भूत्वाथ वामन इमामहरद् बले: क्ष्मांयाच्ञाच्छलेन समदाददिते: सुतेभ्य: ॥ २० ॥
ITRANS:
devāsure yudhi ca daitya-patīn surārthehatvāntareṣu bhuvanāny adadhāt kalābhiḥbhūtvātha vāmana imām aharad baleḥ kṣmāṁyācñā-cchalena samadād aditeḥ sutebhyaḥ
Translation:
The Supreme Lord regularly takes advantage of the wars between the demons and demigods to kill the leaders of the demons. The Lord thus encourages the demigods by protecting the universe through His various incarnations during the reigns of each Manu. The Lord also appeared as Vāmana and took the earth away from Bali Mahārāja on the plea of begging three steps of land. The Lord then returned the entire world to the sons of Aditi.