Zapata Ramirez, Victor2011-03-06http://revistas.pucp.edu.pe/index.php/quimica/article/view/4737/4781- Periodic Table of Videos (http://www.periodicvideos.com)- MIT Open Courseware (http://www.ocw.mit.edu)- Cambridge Chemistry Challenge (www.c3l6.org)- Periodic Table of Videos (http://www.periodicvideos.com)- MIT Open Courseware (http://www.ocw.mit.edu)- Cambridge Chemistry Challenge (www.c3l6.org) application/pdfspainfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by/4.0info:eu-repo/semantics/articlehttps://purl.org/pe-repo/ocde/ford#1.04.00