Here is a tax apportionment clause from a New York will that was drafted in 2014:
FIRST: I direct that all inheritance, estate, transfer, succession and other death taxes or duties (excluding any generation-skipping transfer tax imposed by Chapter 13 of the Internal Revenue Code, as amended from time to time), together with any interest and penalties thereon, imposed by any jurisdiction whatsoever by reason of my death upon or with respect to any property includible in my estate for the purpose of computing such taxes, whether such property passes under the Will, or otherwise, shall be apportioned among the persons benefitted in the proportion that the value of the property of my estate in which such person benefits bears to the total value of all the property of all persons benefitted (the values as finally determined in any respective tax proceedings being the values to be used for the apportionment of the respective taxes). My Executors shall seek reimbursement for such taxes from the persons benefited to the fullest extent permitted by any applicable law.
The example above has three parts:  It defines the taxes that are to be apportioned,  it provides a method for the appointment, and  it directs the executors to seek reimbursement.
-  Notably, the sample excludes the appointment of any federal GST tax. EPTL 2-1.8(a) is broader because it applies broadly to any “estate or other death tax.
-  The language describing the method of apportionment is directly from EPTL (c)(1).