Talk:touch screen

If "touchscreen" is considered an acceptable alternative, should it be listed? I went ahead and added it using the suggested ordering for additional headers in entry layout explained. Is a reference necessary? Is a reference to Wikipedia wikipedia:Touchscreen acceptable? Is a reference to another online dictionary acceptable? (For example: "touchscreen." The American Heritage® Dictionary of the English Language, Fourth Edition. Houghton Mifflin Company, 2004. 13 Sep. 2006. <Dictionary.com dictionary.reference.com/search?q=touchscreen>).