diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
index 828bd5d..f02f01f 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/AdminController.java
@@ -51,13 +51,14 @@ public class AdminController {
     }
 
     /**
-     * Assign admin role to logged in user or user with @email
-     * If role doesn't exists or user is not a member of this group already, use force=true to create and assign both roles.
+     * Assign admin role to logged-in user or user with @email
+     * If role doesn't exist or user is not a member of this group already, use force=true to create and assign both roles.
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.POST)
     public ResponseEntity<Response> assignRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email,
+                                               @RequestParam(required = false) String identifier,
                                                @RequestParam(value = "force", defaultValue = "false") boolean force) {
-        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email, identifier);
         if (coPersonIds.size() > 0) {
             Integer temp = registryService.getCouId(AuthoritiesUtils.memberRole(type, id));
             if (temp != null || force) {
@@ -98,18 +99,19 @@ public class AdminController {
     }
 
     /**
-     * Remove admin role from logged in user or user with @email
+     * Remove admin role from logged-in user or user with @email
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.DELETE)
-    public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email) {
-        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+    public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id,
+                                               @RequestParam(required = false) String identifier,
+                                               @RequestParam(required = false) String email) {
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email, identifier);
         if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(AuthoritiesUtils.memberRole(type, id));
             if (couId != null) {
                 coPersonIds.forEach(coPersonId -> {
                     registryService.removeAdminRole(coPersonId, couId);
-                    String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
-                    authoritiesUpdater.removeRole(identifier, new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
+                    authoritiesUpdater.removeRole(registryService.getIdentifierByCoPersonId(coPersonId), new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
                 });
                 return ResponseEntity.ok(new Response("Role has been revoked successfully"));
             }
diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
index 5acdf24..d61a533 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/MemberController.java
@@ -90,21 +90,22 @@ public class MemberController {
     }
 
     /**
-     * Assign member role to logged in user or user with @email
+     * Assign member role to logged-in user or user with @email
      * If role doesn't exist, use force=true to create and assign the role
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.POST)
-    public ResponseEntity<Response> assignRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email,
+    public ResponseEntity<Response> assignRole(@PathVariable("type") String type, @PathVariable("id") String id,
+                                               @RequestParam(required = false) String identifier,
+                                               @RequestParam(required = false) String email,
                                                @RequestParam(value = "force", defaultValue = "false") boolean force) {
-        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email, identifier);
         if (coPersonIds.size() > 0) {
             Integer temp = registryService.getCouId(AuthoritiesUtils.memberRole(type, id));
             if (temp != null || force) {
                 Integer couId = (temp != null) ? temp : registryService.createRole(AuthoritiesUtils.memberRole(type, id), "");
                 coPersonIds.forEach(coPersonId -> {
-                    String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
                     registryService.assignMemberRole(coPersonId, couId);
-                    authoritiesUpdater.addRole(identifier, new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
+                    authoritiesUpdater.addRole(registryService.getIdentifierByCoPersonId(coPersonId), new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
                 });
                 return ResponseEntity.ok(new Response("Role has been assigned successfully"));
             }
@@ -114,27 +115,29 @@ public class MemberController {
     }
 
     /**
-     * Remove member role from logged in user or user with @email
+     * Remove member role from logged-in user or user with @email
      * If user is an admin of this group, use force=true to revoke both roles
      */
     @RequestMapping(value = "/{type}/{id}", method = RequestMethod.DELETE)
-    public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id, @RequestParam(required = false) String email,
+    public ResponseEntity<Response> removeRole(@PathVariable("type") String type, @PathVariable("id") String id,
+                                               @RequestParam(required = false) String identifier,
+                                               @RequestParam(required = false) String email,
                                                @RequestParam(value = "force", defaultValue = "false") boolean force) {
-        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email);
+        List<Integer> coPersonIds = registryService.getCoPersonIdsByEmail(email, identifier);
         if (coPersonIds.size() > 0) {
             Integer couId = registryService.getCouId(AuthoritiesUtils.memberRole(type, id));
             if (couId != null) {
                 // If none of the accounts has admin role for this group remove member role
                 if (force || coPersonIds.stream().noneMatch(coPersonId -> registryService.getUserAdminGroup(coPersonId, couId) != null)) {
                     coPersonIds.forEach(coPersonId -> {
-                        String identifier = registryService.getIdentifierByCoPersonId(coPersonId);
+                        String aaiIdentifier = registryService.getIdentifierByCoPersonId(coPersonId);
                         Integer role = registryService.getRoleId(coPersonId, couId);
                         if (force) {
                             registryService.removeAdminRole(coPersonId, couId);
-                            authoritiesUpdater.removeRole(identifier, new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
+                            authoritiesUpdater.removeRole(aaiIdentifier, new SimpleGrantedAuthority(AuthoritiesUtils.manager(type, id)));
                         }
                         registryService.removeMemberRole(coPersonId, couId, role);
-                        authoritiesUpdater.removeRole(identifier, new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
+                        authoritiesUpdater.removeRole(aaiIdentifier, new SimpleGrantedAuthority(AuthoritiesUtils.member(type, id)));
                     });
                     return ResponseEntity.ok(new Response("Role has been revoked successfully"));
                 }
diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/SuperAdminController.java b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/SuperAdminController.java
index 14c0ae2..f479c11 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/SuperAdminController.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/controllers/SuperAdminController.java
@@ -1,6 +1,7 @@
 package eu.dnetlib.dnetrolemanagement.controllers;
 
 import eu.dnetlib.dnetrolemanagement.entities.Response;
+import eu.dnetlib.dnetrolemanagement.entities.User;
 import eu.dnetlib.dnetrolemanagement.exception.ConflictException;
 import eu.dnetlib.dnetrolemanagement.exception.ResourceNotFoundException;
 import eu.dnetlib.dnetrolemanagement.services.RegistryService;
@@ -16,6 +17,7 @@ import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.client.HttpClientErrorException;
 
 import java.util.List;
+import java.util.stream.Collectors;
 
 @RestController
 @RequestMapping("/super")
@@ -90,4 +92,15 @@ public class SuperAdminController {
         }
         throw new ResourceNotFoundException("User has not been found");
     }
+
+    @RequestMapping(value = "/user", method = RequestMethod.GET)
+    public ResponseEntity<List<User>> getUsersByEmail(@RequestParam String email) {
+        return ResponseEntity.ok(registryService.getCoPersonIdsByEmail(email).stream().map(id -> {
+            User user = new User();
+            user.setEmail(registryService.getUserEmail(id));
+            user.setId(registryService.getUserId(id));
+            user.setName(registryService.getUserNames(id));
+            return user;
+        }).collect(Collectors.toList()));
+    }
 }
diff --git a/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java b/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
index e48ffa7..31d9389 100644
--- a/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
+++ b/src/main/java/eu/dnetlib/dnetrolemanagement/services/RegistryService.java
@@ -32,7 +32,7 @@ public class RegistryService {
     /**
      * 1.1 Get CoPersonId by Email
      */
-    public List<Integer> getCoPersonIdsByEmail(String email) {
+    public List<Integer> getCoPersonIdsByEmail(String email, String identifier) {
         if (email != null) {
             List<Integer> coPersonIds = new ArrayList<>();
             Map<String, String> params = new HashMap<>();
@@ -46,11 +46,15 @@ public class RegistryService {
             }
             return coPersonIds;
         } else {
-            Integer coPersonId = getCoPersonIdByIdentifier();
+            Integer coPersonId = identifier != null ? getCoPersonIdByIdentifier(identifier): getCoPersonIdByIdentifier();
             return (coPersonId != null) ? Collections.singletonList(coPersonId) : new ArrayList<>();
         }
     }
 
+    public List<Integer> getCoPersonIdsByEmail(String email) {
+        return getCoPersonIdsByEmail(email, null);
+    }
+
     /**
      * 1.2 Get CoPersonId by AAI identifier
      */