Bhai Hassu, a blacksmith, was a devotee of Guru Nanak. According to Purdtan Janam Sdkhi, he and Bhai Sihari, a washerman, accompanied the Guru during his travel through Kashmir. They recorded in writing the hymns uttered by Guru Nanak during this journey.
1. Vir Singh, Bhai, ed., Puratan Janam Sakhi. Amritsar, 1982
2. Macauliffe, Max Arthur, The Sikh Religion. Oxford, 1909