The Department is not prescriptive about styles. Either an in-text/author-date OR a footnote style can be used. The emphasis is on consistency.
In general APA, Chicago, Harvard or MLA are recommended for in-text/author-date, while Chicago or MLA are recommended for footnote styles.
The Library provides information on styles with specific examples in the citing and referencing tutorial.
What are the key concepts of your topic?
(1) United Nations (2) Future
Are there alternative terms which may also describe the topic?
Construct the search into a logical structure to ensure you retrieve relevant results. For example:
("United Nations" OR "Global organization" OR "World organization") AND ("future Plans" OR prospects OR directions OR models)
All synonyms joined by "OR"; all concepts joined by "AND"