The number 1319 in white appears on recto. The photograph is titled "A family of Guibres" on verso, in what may be Antoin Sevruguin's hand.
Page 102 of "Sevruguin's Iran" published by Barjesteh van Waalwijk van Doorn & Co's Uitgeversmaatschappij in Rotterdam and Zaman Publishers in Tehran. Titled: "A Group of Zoroastrians" with the number "1319" also appears on recto.
A reproduction of this image is located on page 281 of “Antoin Sevruguin: Past and Present” published by The Oriental Institute of the University of Chicago in 2020. The number "1319" also appears on recto.