For examples and help, see the Purdue Online Writing Lab -- Research & Citation Resource
Emory library also provides a guide to citation: https://guides.main.library.emory.edu/citing_your_sources
If you are not sure which citation style to use, this guide has helpful advice structured by discipline. You may also want to check with the intended recipient of your work to see if they have specific style requirements.
Modern Language Association (MLA) style is preferred but ANY style is OK, as long as you are consistent.
Zotero helps you collect, manage, and cite research sources. Zotero allows you to attach PDFs, notes and images to your citations, organize them into collections for different projects, and create bibliographies using Word or Open Office.