1. Barber, J.R., Klarbring, A.: Solid Mechanics and its Applications, vol. 107. Springer, Berlin (2003)
2. Bitsadze, A.V.: Some classes of partial differential equations. In: Zahavi, H. (ed.) Advanced Studies in Contemporary Mathematics, 4th edn, p. xiv+504. Gordon and Breach Science Publishers, New York (1988)
3. Dzhuraev, A.: Methods of singular integral equations. Translated from the Russian; revised by the author. Pitman Monographs and Surveys in Pure and Applied Mathematics, 60. Longman Scientific & Technical, Harlow; copublished in the United States with John Wiley & Sons, Inc., New York, pp. xii+311 (1992)
4. Füter, R.: Analytische Funktionen einer Quaternionen Variablen. Comment Math Helvetici 4, 9–20 (1932)
5. Gr, M., Théodoresco, N.: Functions holomorphes dans l’espace. Math. Cluj 5, 142–159 (1931)