J24, J64, J68, M53
J13, J16, J22, M53, M54
M53
J24, M53
M53 ; J24; C93
O33, C93, M53, D91, J24
D91 D12 D83 L81 M37
and Knowledge; Communication; Belief; Unawareness), L81 (Retail and Wholesale Trade; e-Commerce), L86 (Information Goods and Services, Internet Content)
O33; D83: O16; L14; O17; L81
I20, J24, M53, M12