libslepc-real3.20-dev binary package in Ubuntu Oracular amd64

 SLEPc is a software library for the solution of large scale sparse eigenvalue
 problems on parallel computers. It is an extension of PETSc and can be used
 for either standard or generalized eigenproblems, with real or complex
 arithmetic. It can also be used for computing a partial SVD of a large,
 sparse, rectangular matrix.
 .
 This package contains the static libraries, shared links, and header files
 for SLEPc 3.20 with real numbers.

Source package