The Grade Restriction Rule

          @misc{ scivideos_strings:20151016,
            doi = {},
            url = {https://youtu.be/ul2FhktKkT0?list=PL04QVxpjcnjitWcPcsIqJh4pNB3V40Exv},
            author = {},
            keywords = {},
            language = {en},
            title = {The Grade Restriction Rule},
            publisher = {},
            year = {},
            month = {},
            note = {strings:20151016 see, \url{https://scivideos.org/index.php/strings-conferences/20151016}}
          }