Berdinskiĭ, D. A.; Taĭmanov, I. A. Surfaces of revolution in the Heisenberg group and the spectral generalization of the Willmore functional. (Russian, English) Zbl 1164.53372 Sib. Mat. Zh. 48, No. 3, 496-511 (2007); translation in Sib. Math. J. 48, No. 3, 395-407 (2007). MSC: 53C42 22E25 58E30 58J50 PDFBibTeX XMLCite \textit{D. A. Berdinskiĭ} and \textit{I. A. Taĭmanov}, Sib. Mat. Zh. 48, No. 3, 496--511 (2007; Zbl 1164.53372); translation in Sib. Math. J. 48, No. 3, 395--407 (2007) Full Text: arXiv EuDML EMIS
Berdinskiĭ, D. A.; Taĭmanov, I. A. Surfaces in three-dimensional Lie groups. (Russian, English) Zbl 1117.53045 Sib. Mat. Zh. 46, No. 6, 1248-1264 (2005); translation in Sib. Math. J. 46, No. 6, 1005-1019 (2005). MSC: 53C42 22E15 37K25 58J60 PDFBibTeX XMLCite \textit{D. A. Berdinskiĭ} and \textit{I. A. Taĭmanov}, Sib. Mat. Zh. 46, No. 6, 1248--1264 (2005; Zbl 1117.53045); translation in Sib. Math. J. 46, No. 6, 1005--1019 (2005) Full Text: arXiv EuDML EMIS