“The Role of Job Enrichment in Building Differentiation Strategy Service: Analytical Exploratory Study of the Views of a Sample of the General Managers and Heads of Departments and Officials of the People in the General Establishment of Civil Aviation”. Journal of Accounting and Financial Studies ( JAFS ), vol. 10, no. 31, Feb. 2019, https://doi.org/10.34093/jafs.v10i31.374.