Shiva Purana

siva.sh/siva-purana/rudra-samhita/11/34

आचमनत्रयं कृत्वा प्रक्षाल्य च पुनः करौ ।। प्राणायामत्रयं कृत्वा मध्ये ध्यायेच्च त्र्यम्बकम् ।। ३४ ।।

sanskrit

After performing the ritual of sipping water (Achamana), one should cleanse their hands. Then, performing the three rounds of Pranayama (breathing exercises), one should meditate on Lord Trimbakeshwar (a form of Shiva).

english translation

AcamanatrayaM kRtvA prakSAlya ca punaH karau || prANAyAmatrayaM kRtvA madhye dhyAyecca tryambakam || 34 ||

hk transliteration by Sanscript