Double Arrow

Some articles on double, double arrow, arrow:

National Rail - Design and Marketing
... However, National Rail continues to use BR's famous double-arrow symbol, designed by Gerald Burney of the Design Research Unit ... The trademark rights to the double arrow symbol remain state-owned, being vested in the Secretary of State for Transport ... their "advertisement" to appear on traffic signs, whereas the double arrow was already prescribed for indicating a "railway station" ...
Accessibility Relation - Basic Review of (Propositional) Modal Logic
1st Modal Axiom (Duality) The double arrow stands symbolizes 'if and only if,' 'necessary and sufficient' conditions ... Aside from 'necessary and sufficient,' the double arrow represents equivalence between the meaning of two statements, the statement to the left and the ... statement involving 'necessity' on the left side of the double arrow is equivalent to the statement about the negation of 'possibility' on the right ...
List Of Unicode Characters - Supplemental Arrows-A
... Description U+27F0 ⟰ Upward quadruple arrow U+27F1 ⟱ Downward quadruple arrow U+27F2 ⟲ Anticlockwise gapped circle arrow U+27F3 ⟳ Clockwise gapped circle arrow U+27F4 ...

Famous quotes containing the words arrow and/or double:

    It is easy to dodge a spear in the daylight, but it is difficult to avoid an arrow in the dark.
    Chinese proverb.

    On the death of a friend, we should consider that the fates through confidence have devolved on us the task of a double living, that we have henceforth to fulfill the promise of our friend’s life also, in our own, to the world.
    Henry David Thoreau (1817–1862)