Best One-Sided L1-Approximation by Blending Functions of Order (2, 2). - Dimiter Dryanov; Petar Peynov Petrov (J. Approx. Theory, 2002)

A note on Bernstein and Markov type inequalities. - Dimiter Dryanov; Richard Fournier (J. Approx. Theory, 2005)

Interpolation and L1-approximation by trigonometric polynomials and blending functions. - Dimiter Dryanov; Petar Peynov Petrov (J. Approx. Theory, 2012)