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Yordan Tabov (born 1946 in Sofia) is a Bulgarian mathematician with academic Degrees: Doctor of Pedagogical Sciences (2007), PhD in Mathematics (MGU, Moscow, 1974); he is also recipient of The Paul Erdős Award (for significant contributions in mathematical education). His research interests include differential equations, geometry, didactics of mathematics, informatics and applications of mathematics and computer methods in the humanities; the focus of his research activity during the last 20 years was namely the last of the fields mentioned above.
Nikolai Prodanov, Yordan Tabov and Kl.Vassilev. The Reviving History of Dr. Gancho Tsenov. Sofia, 2001, Институт за исторически изследвания − Българска академия на науките, Исторически преглед, 2002, Issue No: 5-6, pp. 253−261, Language: Bulgarian.
Faires, J. Douglas (2006), "Sequences and Series", First Steps for Math Olympians, The Mathematical Association of America, pp. 127–134, doi:10.5948/9781614444046.013, ISBN9781614444046