memory reference instruction
Institute for Reference Materials of Environmental Protection Ministry
bridge installation instruction
filter installation instruction
installation instruction
Institution institution
inertial [reference] frame， inertial [reference] system
optical reference filter wavelength standard reference material
one-address instruction; single address instruction
Oral instruction; Oral teaching; Verbal instruction
Oral teaching; Oral instruction; Verbal instruction
Verbal instruction; Oral instruction; Oral teaching
(thermo) reference material
137Cs reference inventory
3D forward looking reference map