Online or print materials that you refer to briefly but do not necessarily read from cover to cover to get background information or statistical information on your topic are sometimes called reference sources, reference materials, or reference works.
Reference sources may be:
Encyclopedia of Careers and Vocational Guidance by 
Occupational Outlook Handbook 2014-2015 by
Written by the U.S. Department of Labor, the Occupational Outlook Handbook 2014#150;2015 is designed to provide valuable, up-to-date assistance to individuals making decisions about their futures. Accompanying each profession are descriptions of the nature of the work, work environment, and the required qualifications, training, and education, as well as job earnings, related occupations. The book includes details on more than 250 occupations--that’s 90 percent of the jobs available in the United States. It also includes job search methods and job outlook. Keep up in the scramble to stay afloat in the waning job market by staying informed as you plan your training and career.
Career Information Center by
Continues to serve as one-stop resource for librarians, counselors, educators, and other job information providers for more than 20 years. Provides most current information available on nearly 700 careers to people at all stages of career development, including 320 detailed profiles of new and emerging jobs that are not included in competitor titles. New: Most job profiles contain MLA-style citations of books, audio/visual materials, and organizations that serve as additional job-specific resources
Careers and Occupations by