The Antonsen - Bormann idea was originally proposed by these authors for theView original: http://arxiv.org/abs/1202.2946
computation of the heat kernel in curved space; it was also used by the author
recently with the same objective but for the Lagrangian density for a real
massive scalar field in 2 + 1 dimensional curved space. It is now reworked here
with a different purpose - namely, to determine the zeta function for the said
model using the Schwinger operator expansion.