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You're going to need this: https://en.wikipedia.org/wiki/Ink_eraser https://en.wikipedia.org/wiki/Ink_eraser (We called it 'ink killer' in school, you were how
by kaybe 7y ago
You're going to need this: https://en.wikipedia.org/wiki/Ink_eraser https://en.wikipedia.org/wiki/Ink_eraser
(We called it 'ink killer' in school, you were however not allowed to use it the first few years after switching to ink from pencil.)
addendum: And you can get ballpens with the ink as well.