diff --git a/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java b/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
index f33f911274..9d5d094875 100644
--- a/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
+++ b/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
@@ -103,5 +103,80 @@ public class CombiningPublishersTest {
             .expectNext(5)
                         .verifyComplete();
     }
-
+    
+    @Test
+    public void testMergeSequential() {
+        Flux<Integer> fluxOfIntegers = Flux.mergeSequential(
+                evenNumbers, 
+                oddNumbers);
+        
+        StepVerifier.create(fluxOfIntegers)
+        .expectNext(2)
+        .expectNext(4)
+        .expectNext(1)
+        .expectNext(3)
+        .expectNext(5)
+        .expectComplete()
+        .verify();
+    }
+    
+    
+    @Test
+    public void testMergeDelayError() {
+        Flux<Integer> fluxOfIntegers = Flux.mergeDelayError(1, 
+                evenNumbers.delayElements(Duration.ofMillis(500L)), 
+                oddNumbers.delayElements(Duration.ofMillis(300L)));
+        
+        StepVerifier.create(fluxOfIntegers)
+        .expectNext(1)
+        .expectNext(2)
+        .expectNext(3)
+        .expectNext(5)
+        .expectNext(4)
+        .expectComplete()
+        .verify();
+    }
+    
+    @Test
+    public void testMergeWith() {
+        Flux<Integer> fluxOfIntegers = evenNumbers.mergeWith(oddNumbers);
+        
+        StepVerifier.create(fluxOfIntegers)
+        .expectNext(2)
+        .expectNext(4)
+        .expectNext(1)
+        .expectNext(3)
+        .expectNext(5)
+        .expectComplete()
+        .verify();
+    }
+    
+    @Test
+    public void testZip() {
+        Flux<Integer> fluxOfIntegers = Flux.zip(
+                evenNumbers, 
+                oddNumbers, 
+                (a, b) -> a + b);
+        
+        StepVerifier.create(fluxOfIntegers)
+        .expectNext(3)
+        .expectNext(7)
+        .expectComplete()
+        .verify();
+    }
+    
+    @Test
+    public void testZipWith() {
+        Flux<Integer> fluxOfIntegers = evenNumbers
+                .zipWith(oddNumbers, 
+                (a, b) -> a * b);
+        
+        StepVerifier.create(fluxOfIntegers)
+        .expectNext(2)
+        .expectNext(12)
+        .expectComplete()
+        .verify();
+    }
+    
+    
 }