"The firm of Shepherd and Robertson appears to have started trading in Agra in about 1862, moving to Simla in 1864. At around this time the partnership of Howard, Bourne and Shepherd was formed in Allahabad, but soon moved to Simla, and presumably the firm of Shepherd and Robertson was then dissolved. It is likely that the stock of Shepherd and Robertson was absorbed by Bourne and Shepherd since prints signed by Shepherd and Robertson certainly later appear in the Bourne and Shepherd catalogue." - http://www.lib.cam.ac.uk/rcs_photographers/entry.php?id=416, 11.08.2018
"In 1862, the firm of Shepherd & Robertson was founded in Agra, India, by Charles Shepherd and Arthur Robertson. Samuel Bourne joined the firm in 1864, when the business relocated to Simla, India. Ca. 1864-1865, the firm possibly changed its name to "Howard, Shepherd and Bourne". The firm operated until 1870." - ulan, 11.08.2018
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