Map str_name from another table using my cd_label in NHibernate

Question

I want to map an entity from database, but I can't figure out how do this using NHibernate.

My entity "Module" have just three properties: id, name and a list of "Entities". But my database table have the columns: id, cd_entity, cd_label.

So this is my problem. How can I map the property cd_label (that need join another table TB_LABEL to acquire the str_name) to "Module" property name?