ViewBag

http://www.tutorialsteacher.com/mvc/viewbag-in-asp.net-mvc

https://www.codeproject.com/Articles/476967/What-is-ViewData-ViewBag-and-TempData-MVC-Option

Map Path

http://yassershaikh.com/server-mappath-in-asp-net-aspx-mvc-mvc-3-and-net-framework/

http://www.codeflair.net/2014/01/21/how-to-use-server-mappath-in-asp-net-mvc-4/

Bootstrap 4

https://getbootstrap.com/docs/4.0/components/forms/

AntiForgeryToken

http://blog.stevensanderson.com/2008/09/01/prevent-cross-site-request-forgery-csrf-using-aspnet-mvcs-antiforgerytoken-helper/

https://www.codeproject.com/script/articles/articleversion.aspx?aid=266065&av=395284

Html Helper

https://social.technet.microsoft.com/wiki/contents/articles/34915.html-action-and-html-renderaction-in-asp-net-mvc.aspx