I just googled a bit, but you probably just found the same stuff 
:
What we know of it is that it dealt with contrapost and I read somewhere that Botticelli’s Venus was painted with some information from that canon.
“Greek sculptor Polykleitos gave a sense of proportions of human figure in treatise “Canon” that was practically embodied in his sculpture “Doryphoros”.”
“Polykleitos’ book is lost, but we know from other writers who refer to him
that he used some form of a module system:
He used one part of the body (we don’t know what part) as a basic unit of measure
and measured out the rest of his sculptures of the human body in terms of that module”
"The possibility of some link between Polykleitos (or Polyclitus) and the Pythagoreans was suggested already by Diels in 1889. Raven (1951) presented his arguments that probably there was a Pythagorean source where the Canon of Polyclitus was summarized and this work was used by both Vitruvius and Galen. Pollitt (1974, p. 18-21), continuing Raven’s work, went even further and suggested that this link was mutual. Specifically, Polykleitos was influenced by, and perhaps contributed to, the Pythagorean doctrine of number and symmetria (commensurability). The latter view has got a further support by Stewart (1978, pp. 127 and 131).
Raven, J. E. (1951) Polyclitus and Pythagoreanism, Classical Quarterly, 45 [= New Series, Vol. 1], 147-152.
Pollitt, J. J. (1974) The Ancient View of Greek Art: Criticism, History, and Terminology, New Haven, Connecticut: Yale University Press. [See the chapter “Polyclitus’s Canon and the idea of symmetria”, pp. 14-22].
Stewart, A. F. (1978) The canon of Polykleitos: A question of evidence, Journal of Hellenic Studies, 98 122-131."