U01:%x[0,0]
U02:%x[-1,0]
U03:%x[1,0]
U04:%x[-1,0]/%x[0,0]
U05:%x[0,0]/%x[1,0]

U06:%x[0,1] # lowercased token
U07:%x[0,2] # is it a first name?
U08:%x[0,3] # last?
U09:%x[0,4] # date
U010:%x[0,5] # place
U011:%x[0,6] # publisher
U012:%x[0,7] # year?
U013:%x[0,8] # pages?
B