Please note that you don't need to give references to standard software and programming languages, such as Windows Excel and Word, Java, Adobe Photoshop or SPSS. 

• Write any version number in parentheses after the title.
• Write a descriptor of the item in square brackets after the title and version number.
• Write the publisher name, or, if it is available online, provide a link rather than the publisher name. 
• Titles are not in italics.

References:

Miller, M. E. (1993). The interactive tester (Version 4.0) [Computer software]. Psytek Services.

If the software is available online, provide the URL instead of the publisher name:

St. James, J., Schneider, W. & Eschman, A. (2003). PsychMate Student Guide (Version 2.0) [Computer software].  http://www.pstnet.com/products/PsychMate/default.htm

In-text citation:

• (Miller, 1993)
• (St. James, Schneider, & Eschman, 2003)