D. Jukic et R. Scitovski, The best least squares approximation problem for a 3-parametric exponential regression model, ANZIAM J, 42, 2000, pp. 254-266
Given the data (p(i), t(i), f(i)), i = 1,..., m, we consider the existence
problem for the best least squares approximation of parameters for the 3-pa
rametric exponential regression model. This problem does not always have a
solution. In this paper it is shown that this problem has a solution provid
ed that the data are strongly increasing at the ends.