Secondary Sources

Primary Main Tertiary

 Secondary literature sources, including indexes and abstracts, encyclopedias, handbooks, reviews, and other reference sources, facilitate the assimilation of information originally disseminated through the primary literature. They integrate and improve access to the ever-increasing body of primary literature by organizing, repackaging, compiling and editing primary sources. The table below describes several types of secondary sources that will be useful for science research.

The reference section of Musselman Library contains many secondary sources for each of the science disciplines. To identify secondary sources appropriate for a particular discipline or topic, consult guides to the literature of that discipline, and library catalogs.

Literature Type
Indexes and Abstracts Indexes provide the most efficient means of subject or author access to science information published in widely-dispersed primary literature. Relevant citations to works on a subject include such information as the title and author of the article, the title, volume, issue, and publication date of the periodical, and the pages on which the article appears.

Abstracts are extensions of indexes which include a summary, or abstract, of the article. Abstracts often provide enough information to determine whether or not the entire article is needed.

Indexes and Abstracts may be multidisciplinary in their coverage, provide comprehensive coverage of a major discipline, or focus on a narrow subdiscipline.

Some indexes are intended for use by a lay audience, covering a very limited number of popular periodicals. Other indexes and abstracts are intended for professionals in a field of science, and cover an extensive list of peer-reviewed journals as well as review literature, conference proceedings, patents, and other primary sources.

The classified subject heading arrangement of abstracts tends to be more complex than the simple alphabetical arrangement of indexes. Abstracts often provide multiple access points, including biosystematic names, molecular formulas, geographic locations, chemical names, and a variety of classification codes. Searching the controlled vocabulary of some abstracting tools is facilitated by the use of a thesaurus.
Indexes and abstracts are available in both print and electronic formats, although electronic databases are more convenient and provide more flexibility in searching.
Citation Indexes Citation indexing is based upon the premise that there is usually a direct subject relationship between previously published articles that are cited in a new article, and the subject of the new article. A record in a citation index includes the references cited in the bibliography of the article. These cited references are searchable and provide access to newer articles that are related to the subject of the original article.
Bibliographies A bibliography is a collection of citations to information sources on a particular topic. A bibliography may cover a broad subject area or focus on a very narrow topic. It may be limited by date, language, country of publication, format, or other characteristics.

Bibliographies appear at the ends of books, book chapters, journal articles, or encyclopedia articles. Long bibliographies are often published as separate books. The arrangement of a bibliography depends on its length and purpose. It may be a simple list arranged alphabetically by author, or it may be arranged by subject headings and subheadings, date, format, or a combination of characteristics.

Bibliographies are important because they save the researcher time in locating at least some of the valuable resources needed for his or her project.

Access to bibliographies depends on the format in which they appear. Bibliographies appearing in journal articles can be accessed using periodical indexes. Those published as a book can be located using a library catalog.
Atlases Atlases are collections of maps, charts, or plates illustrating a particular subject. In addition to geographical atlases, which illustrate geographical information of the earth and space, biomedical atlases consist of charts and plates which locate body parts in three dimensions.
Biographical Sources
Biographical information appears in a number of different kinds of sources, including books, periodicals, encyclopedias and newspapers. Single- or multi-volume collections of biographical information may provide very basic data (name, date of birth, address, employment, education) or may devote several pages to an individual, providing an account of his or her career, education, accomplishments, and significance in their field.

Techniques for locating biographical information depend upon the format in which such information is published. Consult periodical indexes, newspaper indexes, and indexes specific to biographical sources. Also consult library catalogs, encyclopedias and biographical dictionaries.
Dictionaries The primary purpose of science and technology dictionaries is to provide definitions of scientific and technical terms. They may cover all fields of science and technology, or they may be more narrowly focused.
Encyclopedias Encyclopedias often provide a good starting point for research. They are usually arranged alphabetically by topic, but some are arranged by a classified system.

Always consult the index for access to different aspects of a topic that may be treated in different articles.

Most encyclopedia articles also include a brief bibliography of sources for additional reading.
Handbooks Handbooks are single- or multi-volume collections of data and descriptive text that are designed to provide a quick reference source of useful data for experts in a particular field. Information may be presented in charts, tables, graphs, glossaries, and detailed discussions. They may also include bibliographic references to the primary literature and detailed indexes.
Reviews of the Literature Reviews of the literature survey the important primary literature sources and other works on a particular topic, usually over a given time span. They provide the bibliographic information needed to find the original works, and summarize the most important points about advances in that period.

Reviews are important for researchers because they save them the time it would take to search a large body of literature for the most significant items. They also provide students with an excellent starting point for their research.

Reviews may appear in book form in such series as Annual Reviews of..., Progress in..., or Advances in... . Some journals are devoted entirely to reviews of the literature, while others may include a review article in an issue along with research articles.

A thesaurus is a list of controlled vocabulary terms that indicates the relationships of terms to each other within a database. Most list broader, narrower, and related terms. Definitions and scope notes may be included. Thesauri exist in both print and electronic formats.

Using a thesaurus assists a searcher in selecting the most effective terms for retrieving the desired information in a print or electronic index.

Treatises A treatise is a complete, authoritative summary covering an entire subject or field. It contains a detailed bibliography of primary sources from which the information was gathered.