Sog-po-bstan-dar in his mKhas pa’i kha rgyan (p. 179) mentions a certain work with the title Yi ge’i bshad pa rig pa’i sgo ’byed by one sNgags-ban Grub-phug-pa. The editors and compilers of the volume which includes the mKhas pa’i kha rgyan could not identity the work. I have no clue either. But I cannot help wondering if sNgags-ban Grub-phug-pa refers to the famous rNying-ma master gSang-bdag sGro-phug-pa alias Zur Shākya-seng-ge (1074–1134). One can imagine how sGro-phug-pa could easily be mistaken for Grub-phug-pa. But no work of such kind ascribed to gSang-bdag sGro-phug-pa is known to me.