Suraj Prakash, also called Gurpartāp Sūraj Granth, is a popular and monumental hagiographic text about Sikh Gurus written by Kavi Santokh Singh and published in 1843 CE. It consists of life legends performed by Sikh Gurus and historic Sikhs such as Baba Banda Bahadur in 51,820 verses (60,000 when including Nanak Prakash). Most modern writing on the Sikh Gurus finds its basis from this text. Wikipedia