add source link to vulkan specs

diff --git a/zfpacc_proposal.mdwn b/zfpacc_proposal.mdwn
index d528ac46e3c3bfa74e4097904a09c201726160a7..eac608fccb5e192485481254ca8c9e06cb403b26 100644 (file)
--- a/zfpacc_proposal.mdwn
+++ b/zfpacc_proposal.mdwn
@@ -157,6 +157,9 @@ Vulkan requires full ieee754 precision for all F/D instructions except for fdiv
 
 https://www.khronos.org/registry/vulkan/specs/1.0/html/vkspec.html#spirvenv-precision-operation
 
+Source is here:
+<https://github.com/KhronosGroup/Vulkan-Docs/blob/master/appendices/spirvenv.txt#L1172>
+
 OpenCL slightly different, suggest adding as an extra entry.
 
 https://www.khronos.org/registry/OpenCL/specs/2.2/html/OpenCL_Env.html#relative-error-as-ulps