Search algorithms & popularity factors: link, social, click, blog, industry. Since modern search engines are concerned with popularity and not direct relevancy, & big firms up the price of text link buying beyond affordability...
M. Smith, and P. Sainfort. International Journal of Industrial Ergonomics, 4 (1):
67-79(1989)Article argues that employee health can be improved by balancing stressful aspects of work with other job elements..
R. Golbeck, and G. Kiczales. VMIL '07: Proceedings of the 1st workshop on Virtual machines and intermediate languages for emerging modularization mechanisms, page 2. New York, NY, USA, ACM, (2007)