ri'arxu'a lujvo

x1=xu1 declares/specifies x2=xu2=r1 causing x3=r2.

The gismu xusra is broader than just declarations. This definition is meant to narrow down or modify xusra for a more declarative, active, authoritative sense, e.g. as in xusra's ‘[can be used for epistemology of authority]’, rather than mere claims or witnesses. See also: zgaxu'a (claim), xu'ai (I declare), xu'asmu (define), ki'irxu'a (assign / designate), te'iski (synonym), tinbe (obey / conform), javni, catni, ponse.

In definition:

xu'ai (exp!)
evidential: I declare - I submit; «ju'a'ei ri'arxu'a»
xu'ainai
evidential: I declare - I submit; «ju'a'ei ri'arxu'a»

In notes:

zgaxu'a
x1=xu1=z1 claims/asserts/states/witnesses/deduces/infers/[observes]/testifies/bears witness that x2=xu2=z2 using senses/means x3=z3 under conditions x4=z4 conforming to x5 (e.g. objective reality, epistimology, logical source, standard, subjective source).