Download and use Zotero for citing sources in APA style.
To get started, create a personal Zotero account on their website: zotero.org.
Open your browser and navigate to zotero.org/download. Start by downloading Zotero 5.0 for your operating system (e.g. Windows). After Zotero 5.0 is installed on your device, open the desktop app and click "Set up syncing". Log-in using your personal Zotero account.
Next, install the Zotero Connector. This add-on or extension will allow you to save sources directly from your browser with a single click of a button. If you are unsure how to add an extension or add-on, more information can be found on the download page on Zotero's website.
Note: You must be using Chrome, Firefox, or Safari to install the Zotero Connector.
You are now ready to start saving sources to your Zotero library. You must have the Zotero Desktop app running and open on your computer for saving to be enabled.
Start by finding a resource that you would like to save. One there, click on the Zotero Connector button that has been added to your browser. The newly installed button will change in appearance depending on the resource you are trying to save, but it will always be in the same location.
Here are some examples showing the different appearances of the Connector button: 
After saving, you will be able to view the saved item in the Zotero desktop app. The saved source displays in the middle of the screen. When you click on it, you will see item information displayed on the right. All items automatically save to "My Library", but you can organize them into different collections (folders).
You can create citations for single sources or multiple sources at the same time. For a single article, right-click on the article you want to cite and select "Create Bibliography from Item".
For multiple items, either ctrl+right-click on the individual sources you need, or right click on the entire collection on the left-hand side of the page.
Once you make your selection, another window will pop up asking you about the format that you would like for the bibliography. Here, you will want to select APA Style 6th edition, as well as the output format (Bibliography + Copy to Clipboard).
When choosing the output method, the easiest method may be to choose "Copy to Clipboard". This copies the bibliography to your computer's clipboard and allows you to paste it into any word processor. Another good option is to "Save as RTF", which stores the bibliography as .rtf file which can be opened by any word processor (e.g. Microsoft Word).
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