• https://dspace.unl.edu.ec//handle/123456789/29342
• https://dspace.unl.edu.ec//handle/123456789/29344
• https://dspace.unl.edu.ec//handle/123456789/29838
• https://dspace.unl.edu.ec//handle/123456789/29343
• https://dspace.unl.edu.ec//handle/123456789/29339
• https://dspace.unl.edu.ec//handle/123456789/29340
• https://dspace.unl.edu.ec//handle/123456789/29863
• https://dspace.unl.edu.ec//handle/123456789/29347
• https://dspace.unl.edu.ec//handle/123456789/29840
• https://dspace.unl.edu.ec//handle/123456789/29345
• https://dspace.unl.edu.ec//handle/123456789/29841
• https://dspace.unl.edu.ec//handle/123456789/29847
• https://dspace.unl.edu.ec//handle/123456789/29346
• https://dspace.unl.edu.ec//handle/123456789/29842