Schlechtriem, Peter (ed.), English Commentary on the UN Convention on the International Sale of Goods (CISG), Comment on Art. 55 by Günter Hager, Oxford 1998
462 8"

Article 55 CISG refers to the price generally charged for such goods sold under comparable circumstances. The test is therefore an objective one. A buyer is accordingly protected from a seller's extensive prices, but he does not benefit if the seller in fact has a lower price.22 In practice, determining a price under Article 55 may well involve uncertainties23 since prices generally charged are difficult to establish, in particular for special items. It would be more appropriate to refer to an average price, but Article 55 does not do so.24 Nor is it easy to define the relevant trade.

22 Heuzé, note 351.
23 Enderlein/Maskow/Strohbach, Art 55, note 8.
24 Heuzé, note 351.

Referring Principles
Trans-Lex Principle: IV.6.2 - Subsequent fixing of contract price
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