“…Out of the total papers, eleven articles were from Asia [ 19 , 22 , 25 , 30 , 32 , 33 , 36 , 39 , 41 , 43 , 44 ], eight from Europe [ 15 , 17 , 18 , 20 , 24 , 27 , 38 , 45 ], eleven from North America [ 14 , 16 , 26 , 28 , 29 , 34 , 35 , 37 , 40 , 42 , 46 ], two from South America [ 21 , 31 ] and one from Africa [ 23 ].…”