Payment means in an invoice MUST be coded using UNCL4461 code list
cac:PaymentMeans/cbc:PaymentMeansCode( ( not(contains(normalize-space(.),' ')) and contains( ' 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 74 75 76 77 78 91 92 93 94 95 96 97 ZZZ ',concat(' ',normalize-space(.),' ') ) ) )