Declaring undeclared income in Switzerland

How can I declare income or wealth that I forgot to include on my Swiss tax returns? Can I simply add this to my next tax return?

If you have money or wealth which you have not declared in tax returns, you can declare these at any time. This declaration can accompany your tax return, but it must be made as a separate statement. Just including previously undeclared income or assets in your tax return is not sufficient as this does not give the tax office a clear understanding of what taxes are owed.

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