On approximation of signals in Lip(α,r)-class using the product (N, pn,qn)(E,s)- summability means of conjugate Fourier series: On approximation of signals in $Lip(\alpha,r)$-class. NS [Internet]. 2020 May 27 [cited 2025 Dec. 29];27(2). Available from: https://nonlinearstudies.com/index.php/nonlinear/article/view/1575