https://repositorio.pucp.edu.pe/index/bitstream/handle/123456789/53595/fundamentos%20de%20la%20integracion.pdf?sequence=1&isAllowed=y
22
https://www.escriturayverdad.cl/wp-content/uploads/EnsayosDoctrinalesLuteranos/Fundamentos.pdf
224
https://repository.usta.edu.co/bitstream/handle/11634/13551/Hern%C3%A1ndez%C3%81lvaro2015.pdf?sequence=1
84
https://editorial.unicatolica.edu.co/omp/index.php/Sello_Editorial/catalog/download/94/110/461?inline=1
12