RNG validity error: file ./test/relaxng/tutor8_2_5.xml line 1 element head
Expecting an element title, got nothing
RNG validity error: file ./test/relaxng/tutor8_2_5.xml line 1 element head
Invalid sequence in interleave
RNG validity error: file ./test/relaxng/tutor8_2_5.xml line 1 element head
Element head failed to validate content