2183-184X 2183-184X S2183-184X2021000200004 10.47345/v8n2art2 Portugal 30 09 2021 30 09 2021 8 2 4 25

1 2021 2 2019 3 2015 4 1987 6 2000 7 2005 8 2004 9 1982 10 2002 11 2016 12 2000 13 the ABC Research Group 2002 16 2008 17 2017 12 1 1 3-22 18 2013 19 2007 21 2021 LXII 1 1 603-35 24 2018 25 2015 32 413-50 26 2012 27 2020 28 2014 31 2019 32 2016 33 2019 34 2012 39 2020 40 2008 42 2021 43 2012 44 2009 45 2005 46 2017 47 2019 48 2012 50 2009 52 2007 53 2021 54 2018