Mercado das comunicações na economia nacional [documento eletrónico] : (2014-2018) / Autoridade Nacional de Comunicações
Market review 2018 [documento eletrónico] : of electronic communications & postal services / Hellenic Telecommunications and Post Commission
Annual report 2018 [documento eletrónico] / Swiss Post
Annual Report 2018 [documento eletrónico] : invest and grow / ed. Ericsson
The great reversal : how America gave up on free markets / Thomas Philippon