Numbers and formulae Plugwise protocol

[tinybit]

Hello,

I'm looking through various pieces of code and into the Plugwise protocol.
Apparently everyone uses the following:

1) There are 468.9385193 pulses per kWs.

2) The pulse correction formula is
pulses = (timespan * (((pow(pulses / 1.0 + offnoise, 2.0) * gain_b) + ((pulses / 1.0 + offnoise) * gain_a)) + offtot))

I was hoping someone could tell me if there's any "official" documentation describing and/or confirming these numbers?

Thanks!