Tertiary Sources Tertiary sources are publications that summarize and digest the information in primary and secondary sources to provide background on a topic, idea, or event. Encyclopedias and biographical dictionaries are prime examples of tertiary sources.
From Wikipedia, the free encyclopedia. A value-added service (VAS) is a popular telecommunications industry term for non-core services, or in short, all services beyond standard voice calls and fax transmissions. However, it can be used in any service industry, for services available at little or no cost, to promote their primary business.
Definition of VAS DEFERENS. : a sperm-carrying duct especially of a higher vertebrate that in the human male is a thick-walled tube about two feet (0.61 meters) long that begins at and is continuous with the tail of the epididymis and eventually joins the duct of the seminal vesicle to form the ejaculatory duct.