4. If the simple opinion is not expressed within the time limit set for this purpose by the law or by the deciding body or, in any case, within a reasonable period of time, the administrative deed may be issued without it. Article 21 Revocation 1. 2. The competent body for the revocation of an individual administrative deed is the body that issued it or the body that is competent for its issuance. The procedure provided for the issuance of the deed does not have to be observed for the revocation thereof, unless a legal or illegal deed is being revoked following the assessment of facts. FOURTH CHAPTER ADMINISTRATIVE CONTRACT Article 22 Form The administrative contract is subject to the written form, unless the law stipulates otherwise. The proposal and acceptance of its conclusion may be effected by separate documents. Article 23 Conclusion The administrative contract concluded following a tender or by direct assignment is concluded as of and by service to the interested party of the deed by which the tender or the assignment are completed respectively, unless the law stipulates otherwise. FIFTH CHAPTER ADMINISTRATIVE APPEALS - COMPLAINTS Article 24 Application for remedy - Hierarchical appeal 1. 2. 3. 4. If the relevant provisions does not allow for the possibility to file the special administrative or remedial appeal under the following article, for the restitution of material or moral prejudice of lawful interests caused by an individual administrative deed, the interested party may, for any reason, apply for revocation or amendment thereof (application for remedy) to the administrative authority that issued the deed, or for cancellation thereof (hierarchical appeal) to the superior authority of the authority that issued the deed. The administrative authority to which the said application is submitted should notify its decision to the interested parry within thirty (30) days, unless special provisions stipulate a different time limit. If another administrative authority is competent for the revocation or amendment or cancellation of the deed, the authority to which the application for remedy or the hierarchical appeal was filed should forward it to the competent authority within five (5) days. In this case as well, the competent authority should notify its decision to the interested party within the time limit stated in the previous paragraph. If the deed is cancelled, the case is referred back to the authority that issued the deed, unless the relevant provisions stipulate power of the superior authority for its issuance. 10