3:19  

तस्मादसक्तः सततं कार्यं कर्म समाचर ।
असक्तो ह्याचरन्कर्म परमाप्नोति पूरुषः ॥३- १९॥

tasmaadasaktaH satataM kaaryaM karma samaachara ।

asakto hyaacharankarma paramaapnoti pooruShaH ॥३- १९॥

Source: Automatic ITRANS Transliteration

Therefore, unattached, always perform duties determinedly.
By unattached, steadfast action, a man achieves the foremost.

Source: Milind S. Pandit

Therefore, always perform your duty efficiently and without attachment to the results, because by doing work without attachment one attains the Supreme.

Source: The Bhagavad-Gita: The Sacred Song

Therefore, without being attached to the fruits of activities, one should act as a matter of duty; for by working without attachment, one attains the Supreme.

Source: Bhagavad Gita As It Is