diff --git a/opacclient/libopac/src/main/java/de/geeksfactory/opacclient/apis/SLUB.kt b/opacclient/libopac/src/main/java/de/geeksfactory/opacclient/apis/SLUB.kt
index 9cea90afa..305100942 100644
--- a/opacclient/libopac/src/main/java/de/geeksfactory/opacclient/apis/SLUB.kt
+++ b/opacclient/libopac/src/main/java/de/geeksfactory/opacclient/apis/SLUB.kt
@@ -159,15 +159,22 @@ open class SLUB : OkHttpBaseApi() {
 
     override fun getResultById(id: String, homebranch: String?): DetailedItem {
         val json: JSONObject
-        val url =
-                if (id.startsWith("id")) {
-                    "$baseurl/$id/"
-                } else {
-                    val noRedirectClient = http_client.newBuilder()
-                            .followRedirects(false)
-                            .build()
-                    httpHead("$baseurl/$id/", "Location", "", noRedirectClient)
-                } + "?type=1369315142&tx_find_find[format]=data&tx_find_find[data-format]=app"
+        val url = when {
+            id.startsWith("id/") ->
+                "$baseurl/$id/"
+            id.startsWith("bc/") || id.startsWith("rsn/") ->
+                http_client.newBuilder()
+                        .followRedirects(false)
+                        .build()
+                        .run {
+                            httpHead("$baseurl/$id/",
+                                    "Location",
+                                    "",
+                                    this)
+                        }
+            else -> // legacy case: id identifier without prefix
+                "$baseurl/id/$id/"
+        } + "?type=1369315142&tx_find_find[format]=data&tx_find_find[data-format]=app"
         try {
             json = JSONObject(httpGet(url, ENCODING))
         } catch (e: JSONException) {
diff --git a/opacclient/libopac/src/test/java/de/geeksfactory/opacclient/apis/SLUBTest.kt b/opacclient/libopac/src/test/java/de/geeksfactory/opacclient/apis/SLUBTest.kt
index 99298c5f3..03038a6fe 100644
--- a/opacclient/libopac/src/test/java/de/geeksfactory/opacclient/apis/SLUBTest.kt
+++ b/opacclient/libopac/src/test/java/de/geeksfactory/opacclient/apis/SLUBTest.kt
@@ -838,6 +838,32 @@ class SLUBGetResultByIdMockTest : BaseHtmlTest() {
         verify(slub).httpGet("https://test.de/id/123/?type=1369315142&tx_find_find[format]=data&tx_find_find[data-format]=app", "UTF-8")
         assertEquals("id/123", actual.id)
     }
+
+    @Test
+    fun testRsnIdentifier() {
+        doReturn("https://test.de/id/123/").`when`(slub).httpHead(Matchers.any(),
+                Matchers.any(), Matchers.any(), Matchers.any())
+        val response = """{"record":{"title":"The title"},"id":"123","thumbnail":"","links":[],"linksRelated":[],
+                            |"linksAccess":[],"linksGeneral":[],"references":[],"copies":[],"parts":{}}""".trimMargin()
+        doReturn(response).`when`(slub).httpGet(Matchers.any(), Matchers.any())
+        val actual = slub.getResultById("rsn/456", null)
+        verify(slub).httpHead(eq("https://test.de/rsn/456/"), eq("Location"), eq(""),
+                argThat(ClientDoesntFollowRedirects()))
+        verify(slub).httpGet("https://test.de/id/123/?type=1369315142&tx_find_find[format]=data&tx_find_find[data-format]=app", "UTF-8")
+        assertEquals("id/123", actual.id)
+    }
+
+    @Test
+    fun testLegacyIdentifier() {
+        // id without prefix, e.g. from old favorites list
+        val response = """{"record":{"title":"The title"},"id":"123","thumbnail":"","links":[],"linksRelated":[],
+                            |"linksAccess":[],"linksGeneral":[],"references":[],"copies":[],"parts":{}}""".trimMargin()
+        doReturn(response).`when`(slub).httpGet(Matchers.any(), Matchers.any())
+        val actual = slub.getResultById("123", null)
+        verify(slub).httpGet("https://test.de/id/123/?type=1369315142&tx_find_find[format]=data&tx_find_find[data-format]=app", "UTF-8")
+        verify(slub, never()).httpHead(any(), any(), any(), any())
+        assertEquals("id/123", actual.id)
+    }
 }
 
 @RunWith(Parameterized::class)