| nssn.org | NSSN: A National Resource for Global Standards |
| copant.org | Pan American Standards Commission (COPANT) |
| standards.com.au | Australia - Standards Australia |
| itu.int | International Telecommunication Union (ITU) |
| iso.org | The International Organization for Standardization [ISO] |
| iso.ch | ISO. International Organization for Standardization |
| iec.ch | International Electrotechnical Commission |
| din.de | DIN Deutsches Institut für Normung e.V. |
| cenorm.be | The European Committee for Standardization (CEN) |
| ansi.org | American National Standards Institute |
| iso.ch | www.iso.ch/ |
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