Life cycle
-
Now
-
00
Preliminary
-
10
Proposal
-
20
Preparatory
-
30
Committee
-
40
Enquiry
-
50
Approval
-
60
Publication
-
90
Review
-
95
Withdrawal
Corrigenda / Amendments
WithdrawnISO/R 91:1970/Add 1:1975
-
00
-
Revised by
WithdrawnISO 91-1:1982
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