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