Giani Gian Singh was a Sikh scholar and martial artist, belong to
Nihang
The Nihang or Akali (lit. "the immortals") is an armed Sikh warrior order originating in the Indian subcontinent. Nihang are believed to have originated either from Fateh Singh and the attire he wore or from the "Akali" (lit. Army of the Immort ...
order, famous for his work on Shastarvidya. He spent 40 years on textual analysis of Guru Granth Sahib from very rare Manuscripts and over a hundred codices (Birs) and published some basic findings.
[Ernest Trumpp and W.H. McLeod as scholars of Sikh history religion and culture, Bhai Trilochan SinghInternational Centre of Sikh Studies, 1994]
His work with Kundan Singh and Randhir Singh research scholar is known as ''Sri Guru Granth Sahib ji dian Santha-Sainchian are Puratan Hathlikhit Pavan Biran de Praspar Path-Bhedan di Suchi'' ( The list of textual variations present in the early sacred manuscripts and printed versions of the Guru Granth Sahib) which was published in 1977.
References
{{Reflist
Indian Sikhs
Nihang