The art of Virtual Analog filter design [pdf] (native-instruments.com)

NI is Native Instruments, has been that way since the late, late 90's in audio circles

Sure in music circles, but National is pretty big in DSP circles and if I just search NI in google, National Instruments is the first 5 results followed by a news story followed by Native Instruments. If you go to NI.com, that's National Instrument's website. If I search for NI DSP, NI analog, or NI filters all return National Instruments top billing.

I think it's reasonable that someone might get confused especially since the PDF (About DSP implementations of Analog Filters) doesn't mention Native.

Always been native instruments in my area. especially simple when commenting on a link from the native instruments website