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4. Directive 1999/93/EC of the European parliament and of the council of 13 December 1999 on a community framework for electronic signatures. Official Journal L 013, 19/01/2000 p. 12 – 20. Available:https://eur-lex.europa.eu/legalcontent/EN/TXT/HTML/?uri=CELEX:31999L0093&from=ES.
5. Regulation (EU) no 910/2014 of the European parliament and of the council of 23 July 2014 on electronic identification and trust services for electronic transactions in the internal market and repealing directive 1999/93/EC. OJ L 257, 28.8.2014, p. 73-114. Available:https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32014R0910&from=EN.