Wiktionary Appendix: <span class="searchmatch">ISO</span> <span class="searchmatch">216</span> <span class="searchmatch">paper</span> <span class="searchmatch">sizes</span> English Wikipedia has an article on: <span class="searchmatch">ISO</span> <span class="searchmatch">216</span> Wikipedia <span class="searchmatch">ISO</span> <span class="searchmatch">216</span> specifies the standard <span class="searchmatch">paper</span> <span class="searchmatch">sizes</span> used in most countries...
which explains the use of "CH" for its <span class="searchmatch">ISO</span> country code, ".ch" for its Internet domain, and "CHF" for the <span class="searchmatch">ISO</span> three-letter abbreviation of its currency...