1. Ad imurthi, M. Struwe.Global compactness properties of semilinear elliptic equation with critical exponential growth, J. Funct. Anal., 175 (2000), 125-167.
2. T. Aubin, Sur la function exponentielle, C. R. Acad. Sci. Paris Sér. A-B, 270 (1970), A1514-A1516.
3. H. Brezis, Functional Analysis, Sobolev Spaces and PDEs, Springer, 2011.
4. L. Carleson, S. Chang.On the existence of an extremal function for an inequality of J. Moser, Bull. Sci. Math., 110 (1986), 113-127.
5. P. Cherrier.Une inégalité de Sobolev sur les variétés riemanniennes, Bull. Sci. Math., 103 (1979), 353-374.