1. L.B. Anderson, A. Constantin, J. Gray, A. Lukas and E. Palti, A Comprehensive Scan for Heterotic SU(5) GUT models, JHEP01 (2014) 047 [arXiv:1307.4787] [INSPIRE].
2. A. Constantin, Y.-H. He and A. Lukas, Counting String Theory Standard Models, Phys. Lett.B 792 (2019) 258 [arXiv:1810.00444] [INSPIRE].
3. M. Cvetič, J. Halverson, L. Lin, M. Liu and J. Tian, Quadrillion F-Theory Compactifications with the Exact Chiral Spectrum of the Standard Model, Phys. Rev. Lett.123 (2019) 101601 [arXiv:1903.00009] [INSPIRE].
4. C. Vafa, Evidence for F-theory, Nucl. Phys.B 469 (1996) 403 [hep-th/9602022] [INSPIRE].
5. D.R. Morrison and C. Vafa, Compactifications of F-theory on Calabi-Yau threefolds. 1, Nucl. Phys.B 473 (1996) 74 [hep-th/9602114] [INSPIRE].