2520-9825 2520-9825 S2520-98252021000200067 10.36716/unitepc.v8i2.86 00 12 2021 00 12 2021 8 2 67 72 1 2010 17 77 77 15-23 2 1999 354 9186 9186 1277-82 3 2016 27 ed 4 2011 22 6 6 258-67 5 2006 3a ed 6 2008 2 3 3 188-92