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Fortran 90 introduces the concept of ``elemental procedures'', which are defined for scalar arguments but may also be applied to conforming array-valued arguments. The latter type of reference to an elemental procedure is called an ``elemental'' reference. Examples are the mathematical intrinsics, e.g. SIN and the intrinsic subroutine MVBITS. However, Fortran 90 restricts elemental reference to a subset of the intrinsic procedures - programmers cannot define their own elemental procedures. We propose that pure procedures may also be referenced elementally, subject to certain additional constraints given below.