Cruz, E. A. (1994). Tracking productivity growth thru the value added productivity measurement: (VAPM) approach: An introduction. Pasig City: Development Academy of the Philippines.

Introduction to productivity measurement -- Why measure productivity -- Linkage between productivity and profitability -- Measures of Output -- Measures of Input -- Concept of value added -- Definition and significance of value added -- Methods of calculating value added -- Subtraction method -- Addition method -- General mechanics of value added productivity measurement (VAPM) -- Definition and significance of VAPM -- Significance of VAPM ratios -- Relationship between profitability and productive ratios -- Analysis of VAPM ratios -- Trend analysis -- Vertical analysis -- Regression analysis -- Benchmarking on wage value added productivity ratio -- Break-even point analysis -- Utilizing results of VAPM for productivity improvement -- Optimum number of employees -- Value added management plan -- Marginal profit approach -- Application of the VAPM approach