56In the present case, it should be noted that paragraphs 61 to 67 of the application contain a summary of the legal arguments by which the applicant challenges by his fourth plea, alleging infringement of the EU rules on the use of languages, the lawfulness of the notice of competition in the light of Council Regulation No 1 of 15 April 1958 determining the languages to be used by the European Economic Community (OJ 1958 L 17, p. 385), as amended by Council Regulation (EU) No 517/2013 of 13 May 2013 adapting certain regulations and decisions in the fields of free movement of goods, freedom of movement for persons, company law, competition policy, agriculture, food safety, veterinary and phytosanitary policy, transport policy, energy, taxation, statistics, trans-European networks, judiciary and fundamental rights, justice, freedom and security, environment, customs union, external relations, foreign, security and defence policy and institutions, by reason of the accession of the Republic of Croatia (OJ 2013 L 158, p. 1) (‘Regulation No 1’), and of the principle of equal treatment. That summary is sufficiently clear and precise to enable the Parliament to prepare its defence and the Court to exercise its power of review. The fourth plea must therefore be declared admissible.