Mostrare como incluir referencias bibliograficas en un documento LaTeX, ademas de los estilos que se pueden utilizar. Como usar Bibtex, con base de datos y sin ellas

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\author{Favian Arenas}

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    \section{Introduccion}

    El problema de complementariedad no lineal \cite{LibroPCNL} surge en diversas aplicaciones como por ejemplo, problemas  de contacto mecanico \cite{arenas2018} y friccion, problemas de mecanica estructural y  diseno estructural, problemas de lubricacion hidrodinamicos \cite{arenas2020}, problemas de equilibrio de trafico , asi como en problemas relacionados con modelos \cite{Andreani2017} de equilibrio economico . 
    
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@article{arenas2018,
  author = {Arenas, F. and Martinez, H and Perez, R.},
  title = {M'{e}todo BFGS estructurado para la estimaci'{o}n de m'{a}xima verosimilitud},
  journaltitle = {Revista de Ciencias},
  year = {2018},
}
@book{LibroPCNL,
  ISBN = {9789585599178},
  author = {Perez, R.  and  Arenas, F. and Martinez, H.  and Arias,C.},
  edition = {1},
  publisher = {Universidad del Valle},
  title = {El problema de complementariedad No lineal: Teoria, aplicaciones y nuevos algoritmos para su solucion},
  year = {2019}
}
@article{arenas2020,
  author = {Arenas, F. and Vivas, H},
  title = {Un software interactivo para el entrenamiento de redes neuronales multicapa usando el metodo secante estructurado},
  ISBN = {1692-7257},
  pages = {85-90},
  journaltitle = {Revista Colombiana De Tecnologias De Avanzada},
  year = {2019},
}
@article{Andreani2017,
  author = {Andreani, Roberto and Martinez, Jose Mario and Ramos, Alberto and Silva, Paulo J. S.},
  title = {Strict Constraint Qualifications and Sequential Optimality Conditions for Constrained Optimization},
  journal = {Mathematics of Operations Research},
  volume = {43},
  number = {3},
  pages = {693-717},
  year = {2018},
  doi = {10.1287/moor.2017.0879},
  URL = {https://doi.org/10.1287/moor.2017.0879},
  eprint = {https://doi.org/10.1287/moor.2017.0879},
  abstract = { Sequential optimality conditions for constrained optimization are necessarily satisfied by local minimizers, independently of the fulfillment of constraint qualifications. These conditions support the employment of different stopping criteria for practical optimization algorithms. On the other hand, when an appropriate property on the constraints holds at a point that satisfies a sequential optimality condition, such a point also satisfies the Karush-Kuhn-Tucker conditions. Those properties will be called strict constraint qualifications in this paper. As a consequence, for each sequential optimality condition, it is natural to ask for its weakest strict associated constraint qualification. This problem has been solved in a recent paper for the Approximate Karush-Kuhn-Tucker sequential optimality condition. In the present paper, we characterize the weakest strict constraint qualifications associated with other sequential optimality conditions that are useful for defining stopping criteria of algorithms. In addition, we prove all the implications between the new strict constraint qualifications and other (classical or strict) constraint qualifications. }
}