The number "95" in white ink appears on recto in what is probably Antoin Sevruguin's hand. The same number in the same location appears in the other gelatin silver print of this image in the Nelson collection.
Page 341 of “Persia Past and Present” by A.V. Williams Jackson which was published by The Macmillan Company in London in 1906. The print is not attributed to Antoin Sevruguin and titled “Opium smokers”.
The same image of this print appears on page 90 of "Sevruguin's Iran" published by Barjesteh van Waalwijk van Doorn & Co's Uitgeversmaatschappij in Rotterdam and Zaman Publishers in Tehran.