The unique material of 35 of Johannes Gennadius’s scrapbooks (photographs, engravings, press clippings, notecards and other ephemera) is available digitally at the Gennadius 
Leo Allatius
Leo Allatius was one of the great scholars of the 17th century, born on the Greek island of Chios in 1586 or 1587. Although he was born into a Greek Orthodox environment, Allatius lived the greater part of his life in Rome as a pious Catholic and signed in Latin or Italian most documents that survive. At the time of his death in 1669, he was Custodian of the Vatican Library. His cultural background, bestriding the Greek and Roman worlds, afforded him a unique view of the traditional question of the union between the Catholic and Orthodox churches. The Gennadius Library collection of Allatius’s work includes at least 40 of the 59 books described in C. Jacono’s Bibliografia di Leone Allacci (1588-1669), Palermo 1962.