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The NIH Library’s Systematic Review Service can guide you through your entire systematic review process, with software, classes, consultations, and resources.
The Greek letter π is the symbol for the irrational number representing the ratio of the circumference of a circle to its diameter. It is approximately 3.1415926. Pi Day is an annual celebration on March 14th (3/14), with this year’s being a very special Pi Day (3/14/15).