Book citation

An entirely online book presents some new challenges in referencing --- there are no page numbers and no edition numbers. So how do you cite the book? Here is a recommendation example citation:

Hyndman, R.J. and Athanasopoulos, G. (2013) Forecasting: principles and practice. OTexts: Melbourne, Australia. http://otexts.org/fpp/. Accessed on <date>.

To refer to a specific section, use for example

Hyndman, R.J. and Athanasopoulos, G. (2013) Forecasting: principles and practice. OTexts: Melbourne, Australia. Section 2/3. http://otexts.org/fpp/2/3. Accessed on <date>.