When studying antic and medieval literature, we may find many different texts published with the same title, or, in contrary, the same text published with different titles. To avoid confusion, scholars have published claves, which are books listing ancient texts, identifying them by an identifier — a number or a string of text. For example, for early Christianity, we have the Bibliotheca Hagiographica Graeca, the Clavis Apocryphorum Novi Testamenti and other claves. It could be useful to print the identifier of a texts in one specific clavis, or in many claves. The package allows us to create new field for different claves, and to present all these fields in a consistent way.