path	value/explanation	url	count
invalid value (4 variant(s))			4
008/06 (008all06)	" "		1
008/23 (008book23)			1
Leader/08 (leader08)	0		1
773$ind1	" "		1
undefined subfield (2 variant(s))			2
911	#		1
911	a		1
repetition of non-repeatable subfield (1 variant(s))			1
500$a	there are multiple instances		1