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    <tt>Hi,<br>
      <br>
      I have a place that has "by appointment" .. and I have tagged it<br>
      <br>
      open_hours=by appointment<br>
      <br>
      ......<br>
      There is a fair amount of use of 'appointment' for opening hours
      with lots of variety. <br>
      <br>
      Favourites are <br>
      <br>
      on appointment<br>
      by appointment <br>
      <br>
      Few with capitols. <br>
      <br>
      And few with things like <br>
    </tt><a
href="http://taginfo.openstreetmap.org/tags/opening_hours=Mo-Tu%2CTh-Fr%2009%3A00-13%3A00%2C14%3A00-18%3A00%3BWe%2009%3A00-13%3A00%3B%20%22Sa%20by_appointment%22">Mo-Tu,Th-Fr
      09:00-13:00,14:00-18:00;We 09:00-13:00; "Sa by_appointment"</a><br>
    <br>
    <pre>It would be nice to formalise this use on the wiki before it becomes very diverse? </pre>
    <pre>
Perhaps the simple use of 'appointment' without 'by' or 'on' would be simplest? </pre>
    <pre>The above example could become 
<a href="http://taginfo.openstreetmap.org/tags/opening_hours=Mo-Tu%2CTh-Fr%2009%3A00-13%3A00%2C14%3A00-18%3A00%3BWe%2009%3A00-13%3A00%3B%20%22Sa%20by_appointment%22">Mo-Tu,Th-Fr 09:00-13:00,14:00-18:00;We 09:00-13:00; "Sa 09:00-18:00 +_appointment"</a>

To mean that an appointment is required for Saturday between 9 am and 6 pm. 
Thoughts? </pre>
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