There is only a little passage in WWikipedia (https://en.wikipedia.org/wiki/Orthogonal_polynomials) about the history of orthogonal polynomials, namely: "The field of orthogonal polynomials developed in the late 19th century from a study of continued fractions by P. L. Chebyshev and was pursued by A. A. Markov and T. J. Stieltjes. Some of the mathematicians who have worked on orthogonal polynomials include Gábor Szegő, Sergei Bernstein, Naum Akhiezer, Arthur Erdélyi, Yakov Geronimus, Dave Gwyn, Wolfgang Hahn, Theodore Seio Chihara, Mourad Ismail, Waleed Al-Salam, and Richard Askey." I would like to known more details about how this theory and the theory of orthogonal functions envolved along the centuries, but I did not find any reference. Any comments will be appreciated.
Best,
Ricardo.