Various embodiments can be used to process packages or documents that contain markup language describing one or more documents. Markup language descriptions can be processed to identify certain objects that reoccur or are repeated in the markup language description. If a re-occurring or repeating object is encountered in the markup language description, a resource dictionary can be used to catalog such objects and, an associated object model can include, from the resource dictionary, references to a re-occurring or repeating object. By using the resource dictionary as such, memory resources can be conserved when an in-memory representation of the object model is built.