This formula sheet has been originally compiled during the training sessions of the Estonian and Finnish teams (since 1994); actually, the students were the ones who requested it. Now, since I decided to use it as a reference list for the on-line competition "Physics Cup – IPhO2012", I revised it trying to make it more easily understandable, and intend to continue doing so: please keep track of the version number, the current one is 26th June 2013. Also, if you have any suggestions (eg. if some formulations are not clear or you discover a mistake/typo), please let me know.
You can also download Indonesian translation of the formula sheet, which is contributed by Zainal Abidin, and Portuguese translation contributed by Ivan Tadeu Ferreira Antunes Filho.
In addition to the formula sheet, you may want to have a look on the various IPhO study guides at my homepage (not everything is available in English yet). Also, many more IPhO-level physics problems (together with solutions) can be found at the home page of Estonian-Finnish Olympiads.
Jaan Kalda, Academic Committee of IPhO-2012