In the reference list, capitalize the first word of titles of articles, books, reports, webpages, and other works. Also, capitalize the first word of subtitles. 

Example: 

• Democracy in decline: Rebuilding its future

All major words of periodicals (for example journals, magazines and newspapers) are capitalized. (Nouns, verbs, adjectives, adverbs, pronouns, and all words of four letters or more are considered major words).  

Example: 

• International Journal of Theoretical Physics