diff --git a/cmake/modules/int_am.cmake b/cmake/modules/int_am.cmake
index 13f82188..c1d61cd5 100644
--- a/cmake/modules/int_am.cmake
+++ b/cmake/modules/int_am.cmake
@@ -210,7 +210,7 @@ macro(process_integrals_class class)
                 endif()
             endforeach()
 
-            list(JOIN LIBINT2_${class}_MAX_AM "," ${class}_MAX_AM_LIST)
+            list(JOIN LIBINT2_${class}_MAX_AM "," LIBINT_${class}_MAX_AM_LIST)
             set(LIBINT_${class}_MAX_AM "")
         else()
             set(LIBINT_${class}_MAX_AM_LIST "")
@@ -255,7 +255,7 @@ macro(process_integrals_class class)
                 message(FATAL_ERROR "Invalid value for LIBINT2_${class}_OPT_AM (${LIBINT2_${class}_OPT_AM}). LIBINT2_ENABLE_${class} derivative (${LIBINT_INCLUDE_${class}}) requires list length ${_ntokens_xptd_max_deriv}, not ${_ntokens}.")
             endif()
 
-            list(JOIN LIBINT2_${class}_OPT_AM "," ${class}_OPT_AM_LIST)
+            list(JOIN LIBINT2_${class}_OPT_AM "," LIBINT_${class}_OPT_AM_LIST)
             set(LIBINT_${class}_OPT_AM "")
         else()
             set(LIBINT_${class}_OPT_AM_LIST "")