DoubleUpArrow 
DoubleUpArrow[x,y,…]
displays as x⇑y⇑….
Details
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- DoubleUpArrow[x,y,…] has no built-in meaning.
- x⇑y is by default interpreted as DoubleUpArrow[x,y].
- ⇑ can be entered as \[DoubleUpArrow].
Examples
Basic Examples (1)
Wolfram Research (1996), DoubleUpArrow, Wolfram Language function, https://reference.wolfram.com/language/ref/DoubleUpArrow.html.
Text
Wolfram Research (1996), DoubleUpArrow, Wolfram Language function, https://reference.wolfram.com/language/ref/DoubleUpArrow.html.
CMS
Wolfram Language. 1996. "DoubleUpArrow." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/DoubleUpArrow.html.
APA
Wolfram Language. (1996). DoubleUpArrow. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/DoubleUpArrow.html