The connected sum of -manifolds and is formed by deleting the interiors of -Balls in and attaching the resulting punctured Manifolds to each
other by a Homeomorphism
, so

is required to be interior to and bicollared in to ensure that the connected sum is a Manifold.

The connected sum of two Knots is called a Knot Sum.

**References**

Rolfsen, D. *Knots and Links.* Wilmington, DE: Publish or Perish Press, p. 39, 1976.

© 1996-9

1999-05-26