Русско-англо-русский юридический словарь

Price sanctions are used when the parties agree on them. They are also permissible in place of mandatory penalty for breach of contract. The amount is, likewise, to be fixed by the parties (Contract Law § 53). If they do not agree on the amount, then a half of the statutory penalty for the same breach of contract is the amount to be charged. (International Encyclopedia of Comparative Law, Volume 13, Part 1, by Michael A. Schwind)