1. „Alfred Nobel – Biography, „ Horst Kant, in Bulgarian, translation from German, Publ. „House Prosweta,“ Sofia, 1997

  2. „Mathematics in miniatures” , in Bulgarian, translation from german, Publ. House “Nauka i izkustwo”, Sofia, 1985

  3. Das Akademiemitglied S.N.Bernstein und seine Arbeiten zur konstruktiven Funktionentheorie”, in German, translation from Russian, Mathematisches Seminar Giessen – Mitteilungen, 1999

  4. 35th Conference Applications of Mathematics in Engineering and Economics, 2009, Proceedings, Editor, American Institute of Physics Conference Proceedings, vol.1293.

  5. 36th Conference Applications of Mathematics in Engineering and Economics, 2010, Proceedings, Editor, American Institute of Physics Conference Proceedings, vol.1293.

  6. “Complex analysis”, textbook, in Bulgarian, coauthor M. Durcheva, Publ. House TU – Sofia, 2010, available in English at www.math.bas.bg/complan/rkovach/teaching

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