  One of the most widely used methods for determination of the bending
elasticity modulus of model lipid membranes is the analysis of the shape
fluctuations of nearly spherical lipid vesicles. The theoretical basis of this
analysis is given by Milner and Safran. In their theory the stretching effects
are not considered. In the present study we generalized their approach
including the stretching effects deduced after an application of statistical
mechanics of vesicles.
