So it turns out that there are a number of books that discuss the history of the Bukharian Jews including this important turning-point in their history, such as:
- מסע בארץ הקדם by אפרים ניימארק
- מבוכארה לירושלים by גיורא פוזיילוב
- מסירות נפש של יהודי בוכרה by שלמה ניאזוב
- שלוחי ארץ ישראל by אברהם יערי
- תולדות יהודי בוכארה by נסים טג'ר
On whether it is known why Rabbi Maman made this claim, Giyora Pozeilov wrote in his book מבוכארה לירושלים (From Bukhara to Yerushalayim), p. 39:
"לא ידוע לנו אם באמת סבור היה חכם יוסף כי הם מגולי ספרד, או שמא התכוון ביודעין להפיץ בקרבם את מנהגי יהודי ספרד כדי לקשרם אל אחיהם בשאר תפוצות ישראל ולעשותם חטיבה אחת בהלכה ובמנהג."
Translation: "It is not known whether Chacham Yosef truly thought that they were descendants of the exiled from Spain, or perhaps he intended to spread among them the traditions of the Sephardic Jews to connect them to the rest of their brethren in the Jewish diaspora and to make them a unified unit in halacha and tradition."
As a side-note, it turns out that when Rabbi Maman was there, a Yemenite rabbi named Rabbi Zechariah Matzliach was also there trying to spread the Yemenite traditions among the Bukharians, and a rivalry broke out between the two and their students. Whenever the students of Rabbi Maman claimed that prior to his arrival, the Bukharians were illiterate boors, the students of Rabbi Matzliach countered and claimed that it is known there were Bukharian poets in the 18th century, as well as Jews who died as a Kiddush Hashem. Other evidence presented by some of the other authors suggests that the situation was far from being as-bad as described by that one source that states that Rabbi Maman found an illiterate, boorish and practically spiritually-desolate community.