Dehn had studied the squaring problem in 1903 and proved that a rectangle can be squared if and only if its sides are commensurable and that if it can be squared then there are infinitely many perfect squarings.
Dehn had-aral ng squaring problema sa 1903 at na ang isang rectangle ay maaaring squared kung at kapag lamang na gilid nito ay ihambing at na kung ito ay maaaring squared pagkatapos ay may maraming mga perpektong squarings walang hanggan.