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Below you will find a complete set of details for 2 different references / citations that are related to the computation of Cohen's d effect size values for t-tests.

Reference for Citing the Online Calculator

- Soper, D.S. (2021). Effect Size (Cohen's d) Calculator for a Student t-Test [Software]. Available from https://www.danielsoper.com/statcalc

Reference from the Scientific Literature

- Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd Edition). Hillsdale, NJ: Lawrence Earlbaum Associates.

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