Here is the Sanskrit anuvad, Hindi anuvad, and English translation of Moksha-Sanyasa Yoga Chapter 18, Verse 18.6.
Sanskrit
एतान्यपि तु कर्माणि सङ्गं त्यक्त्वा फलानि च । कर्तव्यानीति मे पार्थ निश्चितं मतमुत्तमम् ॥ १८.६ ॥
Hindi
इसलिये हे पार्थ ! इन यज्ञ, दान और तपरूप कर्मों को तथा और भी सम्पूर्ण कर्तव्य कर्मों को आसक्ति और फलों का त्याग करके अवश्य करना चाहिये, यह मेरा निश्चय किया हुआ उत्तम मत है ।
English
However, dear Arjuna, these works of purification should be performed with freedom from attachment to material goods and without expectation of any rewards resulting from these actions. This, O Partha, is My decided and final word.