Barbilian indicated in his paper "Asupra unui principiu de metrizare" that he prefers the term  "Apollonian metric space", and articles from Alan F. Beardon, Frederick Gehring and Kari Hag, Peter A. Häströ, Zair Ibragimov and others use that term. Barbilian made a contribution to the foundations of geometry with his articles in 1940 and 1941 in Jahresbericht der Deutschen Mathematiker-Vereinigung on projective planes with coordinates from a ring. According to Boskoff and Suceavă, this work "inspired research in ring geometries, nowadays associated with his, Hjelmslev’s and Klingenberg’s names." A more critical stance was taken in 1995 by Ferdinand D. Velkamp:  Nevertheless, in 1989 John R. Faulkner wrote an article "Barbilian Planes" that clarified terminology and advanced the study. In his introduction he wrote:   In 1942, Barbilian was named professor at the University of Bucharest, with some help from fellow mathematician Grigore Moisil. As a mathematician, Barbilian authored 80 research papers and studies. His last two papers, written in collaboration with Nicolae Radu, appeared posthumously, in 1962. Barbu was mostly apolitical, with one exception: around 1940 he became a sympathizer of the fascist movement The Iron Guard (hoping to get a professorship if they came to power), dedicating some poems to one of its leaders, Corneliu Zelea Codreanu. In 1940, he also wrote a poem praising Hitler. Ion Barbu died in Bucharest in 1961, and is buried at Bellu Cemetery.