RussGus: 9 hits for Tretter, H.

The Bibliographic Database of German Publication on Russia, the Soviet Union and its Successor States (RussGus) contains about 170.000 records from 1974 to 2003 and collects publications of different document types: books, dissertations and other university publications, articles from journals and newspapers including reviews, maps etc. The lists of personal and geographical subjects are located here and here.

Your search for Tretter, H. provides 9 hits
1	Acta Slavica Concilii Florentini. Narrationes et Documenta, hg v. Johannes Krajcar S.J. Pont. Inst. Orient. Stud. XIV. (Concilium Florentinum Documenta et Scriptores, 9) Tretter, H., in: Ostkirchliche Studien, 1977, S. 209-210 (Rezension)
2	Johann von Gardner: Gesang der russisch-orthodoxen Kirche bis zur Mitte des 17. Jahrhunderts. (Schriften zur Geistesgeschichte des östlichen Europa, 15) Tretter, H., in: Ostkirchliche Studien, 35, 1986, S. 204-205 (Rezension)
3	Käte Gaede: Russisch Orthodoxe Kirche in Deutschland in der ersten Hälfte des 20. Jahrhunderts. (Edition Orthodoxie, 2) Tretter, H., in: Ostkirchliche Studien, 35, 1986, S. 206-207 (Rezension)
4	Sergej Hackel: Pearl of Great Price. The Life of Mother Maria Skobtsova 1891-1945 Tretter, H., in: Ostkirchliche Studien, 32, 1983, S. 60 (Rezension)
5	Der goldene Ring. Das Christentum Rußlands. Text von Desanka Miloševič, Fotos von Nobumitsu Sakuma, Bildlegenden von Sergio Rapetti, Überstzung von Christina Callori-Gehlsen. (Die Welt der Religionen, 8) Tretter, H., in: Ostkirchliche Studien, 32, 1983, S. 210-211 (Rezension)
6	Alexander Elchaninov: The Diary of a Russian Priest. Transl. by Helen Iswolsky. English edition prepared by Kallistos Timothy Ware. With an introduction by Tamara Elchaninov and a Foreword by Dimitri Obolensky. Tretter, H., in: Ostkirchliche Studien, 32, 1983, S. 213-214 (Rezension)
7	Nicholas Arseniev: Mysticism and the Eastern Church. Tretter, H., in: Ostkirchliche Studien, 29, 1980, S. 58-59 (Rezension)
8	Bishop Alexander (Semenoff-Tian-Chansky): Father Ioann of Kronstadt. A Life. Tretter, H., in: Ostkirchliche Studien, 29, 1980, S. 59 (Rezension)
9	Johann von Gardner: Russian Church Singing, Vol.1: Orthodox Worship and Hymnography. Transl. by Vladimir Morosan Tretter, H., in: Ostkirchliche Studien, 29, 1980, S. 211 (Rezension)