Virtual authoring based on the shallow copy technique for a collection of digital documents

Introduces a new authoring mechanism, called virtual authoring, for digital documents. It can be used to create documents by customizing and integrating segments of existing documents. A suitable document model for virtual authoring is discussed, in which two types of virtual documents are declared with possible functions for content development. Shallow copying is introduced as an underlining technique for the construction and maintenance of virtual documents. Documents are reused in developing new documents but are not replicated. The virtual authoring provides a framework for the new information layers on top of the existing collection of digital documents while safeguarding their copyright and ownership