Simplest fractions, simplest Padé fractions, rational approximation.

1. Novak Ya. V., “Some properties of simplest fractions”, BOGOLUBOV READINGS 2007: Programs and Abstracts, INTERNATIONAL CONFERENCE ON COMPLEX ANALYSIS AND WAVE PROCESSES IN MECHANICS, 1, Insitute of Mathematics of the National Academy of Sciences of Ukraine, Kiev, 2007, 23–24
2. Novak Ya. V., “O nailuchshem lokalnom priblizhenii naiprosteishimi drobyami”, Matem. zametki, 84:6 (2008), 882–887    
3. Novak Ya.V., “Kriterii suschestvovaniya nepreryvnykh proizvodnykh u funktsii iz klassa $L_p$ na otrezke”, Sovremennye problemy matematiki, mekhaniki i ikh prilozhenii (mezhdunarodnaya konferentsiya, posvyaschennaya 70-letiyu rektora MGU akademika V. A. Sadovnichego), Universitetskaya kniga, M., 2009, 85
4. Ya. V. Novak, “A criterion of the existence of continuous derivatives for functions of the class $L_p$ on a segment in terms of local approximations by the simplest fractions”, Ukrainian, English summary, Dopov. Nats. Akad. Nauk Ukr., Mat. Pryr. Tekh. Nauky, 2009, no. 5, 36–40  
5. Ya. V. Novak, “Characterization of Hölder-Zigmund classes on interval in terms of local approximations by simplest fractions”, Ukrainian, Zb. Pr. Inst. Mat. NAN Ukr., 3:4 (2006), 239–243  

• Institute of Mathematics, Ukrainian National Academy of Sciences, Kiev