Original: तपः सन्तोष आस्तिक्यं दानम् ईश्वरपूजनम् ।
सिद्धान्तवाक्यश्रवणं ह्रीमती च तपो हुतम् ।
नियमा दश सम्प्रोक्ता योगशास्त्रविशारदैः ॥१८॥ See: Hatha Yoga Pradipika; Note: this free on-line source author lists Tapas twice in the list of niyamas; others list the second last word of second line in the above as जपो, or Japa
Dominik Wujastyk. "The Yoga texts Attributed to Yajnavalkya and their Remarks on Posture". Asian Literature and Translation. 4 (1). Cardiff University Press: 159–164. doi:10.18573/issn.2051-5863.
P. C. Divanji 1954, pp. 105, 118. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, pp. 15–17. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, pp. 21–22. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, pp. 24–26. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, pp. 1–29. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, p. 10. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
P. C. Divanji 1954, pp. 12–14. P. C. Divanji (1954). "Brhad-yogi Yajnavalkya-smrti and Yoga Yajnavalkya". Annals of the Bhandarkar Oriental Research Institute. 34 (1/4): 1–29. JSTOR41784838.
sanskritdocuments.org
॥ योगयाज्ञवल्क्य ॥ Sanskrit text of Yoga Yajnavalkya, SanskritDocuments Archives (2009)
Yajnavalkya tells Gargi in verse 1.55 that one who copulates (मैथुन) only with and always with one's sexual partner is a Brahmachari; see ॥ योगयाज्ञवल्क्य १-५५॥ Sanskrit text of Yoga Yajnavalkya, SanskritDocuments Archives (2009)
॥ योगयाज्ञवल्क्य १-६९ ॥ Sanskrit text of Yoga Yajnavalkya, SanskritDocuments Archives (2009)
॥ योगयाज्ञवल्क्य ॥ Sanskrit text of Yoga Yajnavalkya, SanskritDocuments Archives (2009), pages 6–7