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.
A VAT number, properly called a VAT Registration Number, is an alphanumeric identifier -- consisting of up to 15 characters -- unique to any corporate entity doing business in a European Union country that implements the Value Added Tax system.onducting business does not necessarily mean making sales or purchases of real goods; it is also incumbent upon shippers of goods and organizers of trade shows and conferences to apply for a VAT number.