A  party that with explicit reservation of rights performs or promises
  performance or assents to performance in a manner demanded or offered by
  the other party does not thereby prejudice  the  rights  reserved.  Such
  words   as  "without  prejudice,"  "under  protest,"  or  the  like  are
  sufficient.
Structure New York Laws
Part 3 - Territorial Applicability and General Rules
1-301 - Territorial Applicability; Parties' Power to Choose Applicable Law.
1-302 - Variation by Agreement.
1-303 - Course of Performance, Course of Dealing, and Usage of Trade.
1-304 - Obligation of Good Faith.
1-305 - Remedies to Be Liberally Administered.
1-306 - Waiver or Renunciation of Claim or Right After Breach.
1-307 - Prima Facie Evidence by Third-Party Documents.
1-308 - Performance or Acceptance Under Reservation of Rights.