[1] Popovic, J. and Bojic, D. (2012) A Comparative Evaluation of Effort Estimation Methods in the Software Life Cycle. ComSIS, 9, 455-484.
[2] Moløkken, K. and Jorgensen, M. (2003) A Review of Software Surveys on Software Effort Estimation. International Symposium on Empirical Software Engineering, Rome, 30 September-1 October 2003, 223-230. http://dx.doi.org/10.1109/ISESE.2003.1237981
[3] Boehm, B. (1981) Software Engineering Economics. Prentice-Hall, Upper Saddle River.
[4] Yogesh, K. (2014) A Review on Effort Estimation Techniques used in Software Projects. IJCSMS International Journal of Computer Science & Management Studies, 14, 25-31.
[5] Khatibi, V. and Jawawi, D.N.A. (2010) Software Cost Estimation Methods: A Review. Journal of Emerging Trends in Computing and Information Sciences, 2, 21-29.
[6] Luschen, T. (2012) Fixed Bid vs. Time and Materials—Pros and Cons.
http://www.sundoginteractive.com/sunblog/posts/fixed-bid-vs.-time-and-materials-pros-and-cons
[7] Education Portal, Study.com, Cost Estimating Courses with Training& Degree Program Info.
http://education-portal.com/articles/Cost_Estimating_Courses_Overview_with_Training_and_Degree
_Program_Information.html
[8] Galorath, D. (2008) Step: Estimate Validation and Review.
http://www.galorath.com/wp/step-seven-estimate-validation-and-review.php
[9] Wiegers, K. (2002) Saving for a Rainy Day.
http://www.ibm.com/developerworks/rational/library/content/RationalEdge/apr02/RainyDayApr02.pdf