Image to remember how many days a month has.  This pattern also correlates to the white &amp; black keys of the twelve notes in the musical scale on a piano.<br><br> An alternative hand mnemonic for the months in the Gregorian calendar is here:<br><a href="//commons.wikimedia.org/wiki/File:Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png" class="image" title="File:Calendar Hand Mnemonic - Musical white keys-black keys.png"><img alt="File:Calendar Hand Mnemonic - Musical white keys-black keys.png" src="https://upload.wikimedia.org/wikipedia/commons/thumb/c/cc/Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png/120px-Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png" decoding="async" width="120" height="68" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/c/cc/Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png/180px-Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png 1.5x, https://upload.wikimedia.org/wikipedia/commons/thumb/c/cc/Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png/240px-Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png 2x" data-file-width="3200" data-file-height="1800"></a><br><a href="//commons.wikimedia.org/wiki/File:Calendar_Hand_Mnemonic_-_Musical_white_keys-black_keys.png" title="File:Calendar Hand Mnemonic - Musical white keys-black keys.png">Calendar Hand Mnemonic - Musical white keys-black keys.png</a>
<ul><li><a href="//commons.wikimedia.org/wiki/File:Month_-_Knuckles_(en).svg" title="File:Month - Knuckles (en).svg">File:Month - Knuckles (en).svg</a>: <b>PLEASE COMPLETE AUTHOR INFORMATION</b></li>
<li>derivative work: <a href="//commons.wikimedia.org/wiki/User:Rtyse" title="User:Rtyse">Rtyse</a></li></ul>
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