* Implementation of a parallel matrix class based on PETSc <tt>MatShell</tt> matrix-type.
* This base class implements only the interface to the PETSc matrix object,
* while all the functionality is contained in the matrix-vector
- * multiplication which must be reimplmented in derived classes.
+ * multiplication which must be reimplemented in derived classes.
*
* This interface is an addition to the dealii::MatrixFree class to realize
* user-defined matrix-classes together with PETSc solvers and functionalities.
* See also the documentation of dealii::MatrixFree class and step-37 and step-48.
*
* Similar to other matrix classes in namespaces PETScWrappers and PETScWrappers::MPI,
- * the MatrxiFree class provides the usual matrix-vector multiplication
+ * the MatrixFree class provides the usual matrix-vector multiplication
* <tt>vmult(VectorBase &dst, const VectorBase &src)</tt>
* which is pure virtual and must be reimplemented in derived classes.
* Besides the usual interface, this class has a matrix-vector multiplication