theorem Th50: :: MESFUN16:50

for I, J being non empty closed_interval Subset of REAL
for f being PartFunc of [:RNS_Real,RNS_Real:],RNS_Real
for g being PartFunc of [:REAL,REAL:],REAL
for E being Element of sigma (measurable_rectangles (L-Field,L-Field)) st [:I,J:] = dom f & f is_continuous_on [:I,J:] & f = g & E = [:I,J:] holds
g is E -measurable