“…Although the necessity to go beyond Gaussian chains has been realized for a long time (the seminal paper by Flory [2] appeared more than half a century ago), our knowledge of the mechanical behavior of networks of non-Gaussian chains remains rather limited, due to some difficulties in their mathematical treatment. Serious progress in the analysis of statistics of single polymer chains and membranes with excluded-volume interactions was reached by using the renormalization group technique [3,4,5,6]. These methods, however, have been employed for the analysis of the distribution functions only and have not yet been applied to determine the strain energy of a network, despite the importance of the latter problem for applications, see [7,8] and the references therein, as well as recent publications [9,10,11,12].…”