Renata Freitas <em>et al. </em>2011.
 Use of SPI and CPI in the statistical monitoring of software development projects. In <em>Proceedings of the 10th Brazilian Symposium on Software Quality</em>, June 06, 2011, Curitiba, Brasil. SBC, Porto Alegre, Brasil, 433-440. DOI: <a href="https://doi.org/10.5753/sbqs.2011.15416">https://doi.org/10.5753/sbqs.2011.15416</a>.