1. Bekker PA, Merckens A, Wansbeek TJ (2014) Identification, equivalent models, and computer algebra: statistical modeling and decision science. Academic Press, Cambridge
2. Bollen KA, Bauldry S (2010) Model identification and computer algebra. Sociol Methods Res 39(2):127–156
3. Bound J, Jaeger DA, Baker RM (1995) Problems with instrumental variables estimation when the correlation between the instruments and the endogenous explanatory variable is weak. J Am Stat Assoc 90(430):443–450
4. Bowden J, Jackson C (2015) On the physical interpretation of a meta-analysis in the presence of heterogeneity and bias: from clinical trials to Mendelian randomization. arXiv arXiv:150803768
5. Bowden J, Smith GD, Burgess S (2015) Mendelian randomization with invalid instruments: effect estimation and bias detection through Egger regression. Int J Epidemiol 44(2):512–525