11/30/2008. Remarks by Johan Visschedijk: "Stelia Frati designed a long-range of small aircraft, which were mainly produced by others. The two-seat F.4 Rondone prototype, I-RAID, was built by the aviation section of the Milan Polytechnic, while the nine production aircraft were manufactured by Ambrosini and by Lombardi.

The F.7 was an enlarged three-seat derivate, the prototype I-ADRJ, produced by Societa Aeronautica Italiana Ing. A. Ambrosini & C., was first flown on February 10, 1954, followed by also nine production aircraft, sub-licensed to Legnami Pasotti at Brescia."