Multiple cells, multiple sheets, multiple criteria matching

I have 3 separate workbook tabs. Each with identical headings. I want a separate workbook to look at all 3 to identify each date that each of the original 3 workbooks has a matching date and either the word "Buy" or "Sell".
Example:

Date Yield 1 Yield 2 Yield 3 Buy/Sell
11/20/2014 1.6288 1.6322 1.6328 Buy
1/25/2013 0.8474 0.7081 0.7078 Sell
6/27/2011 1.4496 1.7669 1.7792 Buy


Each workbook would have 100's of dates that say either buy or sell with the same colum headers. I want to know on what matching dates to all 3 either say buy or sell. If it's easier, I can break up into two separate checks one for just "Buy" and one for just "Sell".

Thank you.