  We introduce LCL covers of closed n-dimensional manifolds by n-dimensional
disks and study their properties. We show that any LCL cover of an
n-dimensional sphere can be converted to the minimal LCL cover, which consists
of 2n+2 disks. We prove that an LCL collection of n-disks is a cover of a
continuous n-sphere if and only if the intersection graph of this collection is
a digital n-sphere. Using a link between LCL covers of closed continuous
n-manifolds and digital n-manifolds, we find conditions where a continuous
closed three-dimensional manifold is the three-dimensional sphere. We discuss a
connection between the classification problems for closed continuous
three-dimensional manifolds and digital three-manifolds.
