Nev. Rev. Stat. § 159.107
Except as provided in NRS 159.105, all claims against the protected person, the guardianship estate or the guardian of the estate as such shall be presented to the guardian of the estate. Each such claim shall be in writing, shall describe the nature and the amount of the claim, if ascertainable, and shall be accompanied by the affidavit of the claimant, or someone on behalf of the claimant, who has personal knowledge of the fact. The affidavit shall state that within the knowledge of the affiant the amount claimed is justly due, no payments have been made thereon which are not credited and there is no counterclaim thereto, except as stated in the affidavit. If such claim is founded on a written instrument, the original or a copy thereof with all endorsements shall be attached to the claim. The original instrument shall be exhibited to the guardian or the court, upon demand, unless it is lost or destroyed, in which case the fact of its loss or destruction shall be stated in the claim.
NRS 159.107