1. Adams, W.W., Loustaunau, P.: Analysis of the module determining the properties of regular functions of several quaternionic variables. Pac. J. 196, 1–15 (2001)
2. Adams, W.W., Berenstein, C.A., Loustaunau, P., Sabadini, I., Struppa, D.: Regular functions of several quaternionic variables and the Cauchy–Fueter complex. J. Geom. Anal. 9(1), 1–15 (1999)
3. Andreotti, A., Hill, D.: E. E. Levi convexity and Hans Lewy Problem. Part I: reduction to vanishing theorems. Ann. Sc. Norm. Sup. (3) 26, 325–363 (1972)
4. Andreotti, A., Nacinovich, M.: Complex of partial differential operators. Ann. Sc. Norm. Sup. (4) 26, 553–621 (1976)
5. Baracco, L., Fassina, M., Pinton, S.: An extension theorem for regular functions of two quaternionic variables. arXiv:1810.0895v2 [math.CV], 24 May 2019