See Business Source Ultimate - Select document type Industry Overview and search for "advertising" or "marketing".
Go to WARC - Provides the largest single source of intelligence for the marketing, advertising, media and research communities worldwide.
Go to Statista - Search using keywords such as advertising, ad agencies, marketing to locate a variety of reports and statistics on the topic.
Search in E-Journals these selected periodicals among others:
- Industrial marketing management
- Journal of consumer research
- Journal of interactive marketing
- Journal of international marketing
- Journal of marketing
- Journal of marketing management
