Chemical structure of <a href="https://en.wikipedia.org/wiki/Caffeine" class="extiw" title="en:Caffeine">Caffeine</a>.
<a href="https://en.wikipedia.org/wiki/User:Icey" class="extiw" title="en:User:Icey">Icey</a>, <a href="https://en.wikipedia.org/wiki/User:ClockworkSoul" class="extiw" title="en:User:ClockworkSoul">ClockworkSoul</a>
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