diff --git a/mcc/CMakeLists.txt b/mcc/CMakeLists.txt
index f0e6869..09a5cbb 100644
--- a/mcc/CMakeLists.txt
+++ b/mcc/CMakeLists.txt
@@ -66,7 +66,7 @@ message(STATUS ${ERFA_INCLUDE_DIR})
 
 set(MCC_LIBRARY_SRC1 mcc_generics.h mcc_defaults.h mcc_traits.h mcc_utils.h
      mcc_ccte_iers.h mcc_ccte_iers_default.h mcc_ccte_erfa.h mcc_telemetry.h
-     mcc_pzone.h mcc_pzone_container.h)
+     mcc_angle.h mcc_pzone.h mcc_pzone_container.h)
 set(MCC_LIBRARY1 mcc1)
 add_library(${MCC_LIBRARY1} INTERFACE ${MCC_LIBRARY_SRC1})
 target_compile_features(${MCC_LIBRARY1} INTERFACE cxx_std_23)
diff --git a/mcc/mcc_generics.h b/mcc/mcc_generics.h
index 400fcbd..ae97d1f 100644
--- a/mcc/mcc_generics.h
+++ b/mcc/mcc_generics.h
@@ -527,6 +527,10 @@ struct mcc_pzone_interface_t {
         return std::forward<SelfT>(self).timeFromPZone(std::move(coords), res_time);
     }
 
+    //
+    // NOTE: the method must return:
+    //     point = mcc_celestial_point_c{.pair_kind = MccCoordPairKind::COORDS_KIND_GENERIC, .X = NaN, .Y = NaN}
+    //             if there is no intersection with the zone for given coordinates!
     template <std::derived_from<mcc_pzone_interface_t> SelfT, typename InputT>
     RetT intersectPZone(this SelfT&& self, InputT coords, mcc_celestial_point_c auto* point)
         requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>) &&
diff --git a/mcc/mcc_pzone.h b/mcc/mcc_pzone.h
index 1c94b40..a23e9d4 100644
--- a/mcc/mcc_pzone.h
+++ b/mcc/mcc_pzone.h
@@ -288,7 +288,10 @@ public:
         auto cos_ha = (_sinAlim - sinDec * _sinLat) / cosDec / _cosLat;
 
         if (cos_ha > 1.0) {  // no intersection
-            // compute culmination points?
+            point->pair_kind = MccCoordPairKind::COORDS_KIND_GENERIC;
+            point->X = std::numeric_limits<double>::quiet_NaN();
+            point->Y = std::numeric_limits<double>::quiet_NaN();
+
             return ret;
         }
 
diff --git a/mcc/mcc_pzone_container.h b/mcc/mcc_pzone_container.h
index c023a60..c3215ab 100644
--- a/mcc/mcc_pzone_container.h
+++ b/mcc/mcc_pzone_container.h
@@ -212,6 +212,8 @@ public:
                     }
                 }
             }
+
+            return ret;
         };
 
         return forEach(coords, apply_func, _inZoneFuncCPT, _inZoneFuncEHC);
diff --git a/mcc/tests/ccte_test.cpp b/mcc/tests/ccte_test.cpp
index a8db752..083741a 100644
--- a/mcc/tests/ccte_test.cpp
+++ b/mcc/tests/ccte_test.cpp
@@ -1,4 +1,5 @@
 #include <iostream>
+#include <list>
 
 #include "../mcc_ccte_erfa.h"
 #include "../mcc_pzone.h"
@@ -88,6 +89,16 @@ int main()
 
     // std::vector<std::chrono::duration<double, std::ratio<60>>> vm;
     std::vector<std::chrono::minutes> vm;
+    std::list<bool> lb;
+    bool cf;
+    ret = pzcont.inPZone(eqhrz, &cf, &lb);
+    std::cout << "ret = " << ret.message() << "\n";
+    std::cout << std::boolalpha;
+    std::cout << "IN ZONE 1: " << lb.front() << "\n";
+    std::cout << "IN ZONE 2: " << lb.back() << "\n";
+    std::cout << "COMMON IN ZONE 1,2: " << cf << "\n";
+
+
     ret = pzcont.timeToPZone(eqhrz, &vm);
     std::cout << "ret = " << ret.message() << "\n";
     std::cout << "TIME TO ZONE 1: " << vm[0] << "\n";