Bonfiglioli, Andrea; Lanconelli, Ermanno Subharmonic functions in sub-Riemannian settings. (English) Zbl 1270.31002 J. Eur. Math. Soc. (JEMS) 15, No. 2, 387-441 (2013). Reviewer: Roman Urban (Wrocław) MSC: 31C05 35H20 35J70 PDF BibTeX XML Cite \textit{A. Bonfiglioli} and \textit{E. Lanconelli}, J. Eur. Math. Soc. (JEMS) 15, No. 2, 387--441 (2013; Zbl 1270.31002) Full Text: DOI
Aki, Kunio A note on the generalized Laplacian operators. (English) Zbl 0045.20803 Kōdai Math. Semin. Rep. 1950, 11-12 (1950). PDF BibTeX XML Cite \textit{K. Aki}, Kōdai Math. Semin. Rep. 1950, 11--12 (1950; Zbl 0045.20803) Full Text: DOI