diff --git a/src/main/java/org/cactoos/func/BiFuncOf.java b/src/main/java/org/cactoos/func/BiFuncOf.java
index 5f55bc275..c9266bde8 100644
--- a/src/main/java/org/cactoos/func/BiFuncOf.java
+++ b/src/main/java/org/cactoos/func/BiFuncOf.java
@@ -91,9 +91,7 @@ public BiFuncOf(final BiProc<X, Y> proc, final Z result) {
      */
     public BiFuncOf(final BiFunc<X, Y, Z> fnc) {
         super(
-            (first, second) -> {
-                return fnc.apply(first, second);
-            }
+            fnc::apply
         );
     }
 }
diff --git a/src/main/java/org/cactoos/io/Joined.java b/src/main/java/org/cactoos/io/Joined.java
index 1aa7de201..875ef4995 100644
--- a/src/main/java/org/cactoos/io/Joined.java
+++ b/src/main/java/org/cactoos/io/Joined.java
@@ -65,9 +65,9 @@ public Joined(final Input first, final Input... rest) {
     @Override
     public InputStream stream() throws Exception {
         return new Reduced<InputStream>(
-            (left, right) -> new SequenceInputStream(left, right),
+            SequenceInputStream::new,
             new Mapped<>(
-                input -> () -> input.stream(),
+                input -> input::stream,
                 this.inputs
             )
         ).value();
diff --git a/src/main/java/org/cactoos/scalar/CallableOf.java b/src/main/java/org/cactoos/scalar/CallableOf.java
index d8f25c739..60a720989 100644
--- a/src/main/java/org/cactoos/scalar/CallableOf.java
+++ b/src/main/java/org/cactoos/scalar/CallableOf.java
@@ -50,6 +50,6 @@ public final class CallableOf<T> extends CallableEnvelope<T> {
      * @since 0.41
      */
     public CallableOf(final Scalar<? extends T> slr) {
-        super(() -> slr.value());
+        super(slr::value);
     }
 }
diff --git a/src/main/java/org/cactoos/text/Trimmed.java b/src/main/java/org/cactoos/text/Trimmed.java
index c77a94f45..c3126f5cf 100644
--- a/src/main/java/org/cactoos/text/Trimmed.java
+++ b/src/main/java/org/cactoos/text/Trimmed.java
@@ -40,6 +40,6 @@ public final class Trimmed extends TextEnvelope {
      * @param text The text
      */
     public Trimmed(final Text text) {
-        super(new Mapped(str -> str.trim(), text));
+        super(new Mapped(String::trim, text));
     }
 }
diff --git a/src/test/java/org/cactoos/func/BiFuncOfTest.java b/src/test/java/org/cactoos/func/BiFuncOfTest.java
index 6c41f69aa..4b358f917 100644
--- a/src/test/java/org/cactoos/func/BiFuncOfTest.java
+++ b/src/test/java/org/cactoos/func/BiFuncOfTest.java
@@ -66,9 +66,7 @@ void convertsProcIntoBiFunc() throws Exception {
             "Must convert procedure into bi-function",
             new BiFuncOf<>(
                 new ProcOf<>(
-                    input -> {
-                        done.set(input);
-                    }
+                    done::set
                 ),
                 result
             ),
diff --git a/src/test/java/org/cactoos/func/FlattenedTest.java b/src/test/java/org/cactoos/func/FlattenedTest.java
index 0616403c2..defe75190 100644
--- a/src/test/java/org/cactoos/func/FlattenedTest.java
+++ b/src/test/java/org/cactoos/func/FlattenedTest.java
@@ -39,7 +39,7 @@ void flattens() {
         new Assertion<>(
             "must flatten",
             new Flattened<>(
-                new FuncOf<>(x -> new BoolOf(x))
+                new FuncOf<>(BoolOf::new)
             ),
             new IsApplicable<>("true", true)
         ).affirm();
diff --git a/src/test/java/org/cactoos/func/FuncOfTest.java b/src/test/java/org/cactoos/func/FuncOfTest.java
index 60bbdae1a..7b13ffb14 100644
--- a/src/test/java/org/cactoos/func/FuncOfTest.java
+++ b/src/test/java/org/cactoos/func/FuncOfTest.java
@@ -44,9 +44,7 @@ void convertsProcIntoFunc() throws Exception {
             "Must convert Proc into Func",
             new FuncOf<>(
                 new ProcOf<>(
-                    input -> {
-                        done.set(input);
-                    }
+                    done::set
                 ),
                 result
             ),
diff --git a/src/test/java/org/cactoos/io/LoggingInputStreamTest.java b/src/test/java/org/cactoos/io/LoggingInputStreamTest.java
index 62753cd60..cb9baf75a 100644
--- a/src/test/java/org/cactoos/io/LoggingInputStreamTest.java
+++ b/src/test/java/org/cactoos/io/LoggingInputStreamTest.java
@@ -53,7 +53,7 @@ public int read() throws IOException {
         );
         new Assertion<>(
             "Read doesn't throw an the exception.",
-            () -> stream.read(),
+            stream::read,
             new Throws<>(message, IOException.class)
         ).affirm();
     }
diff --git a/src/test/java/org/cactoos/io/LoggingOutputTest.java b/src/test/java/org/cactoos/io/LoggingOutputTest.java
index 6f3e60c9a..6b36c7889 100644
--- a/src/test/java/org/cactoos/io/LoggingOutputTest.java
+++ b/src/test/java/org/cactoos/io/LoggingOutputTest.java
@@ -65,7 +65,7 @@ public void logWriteZero() throws Exception {
             new TeeInput(
                 new InputOf(""),
                 new LoggingOutput(
-                    () -> new ByteArrayOutputStream(),
+                    ByteArrayOutputStream::new,
                     "memory",
                     logger
                 )
diff --git a/src/test/java/org/cactoos/iterator/PagedTest.java b/src/test/java/org/cactoos/iterator/PagedTest.java
index 22d894bef..08bb5ae0d 100644
--- a/src/test/java/org/cactoos/iterator/PagedTest.java
+++ b/src/test/java/org/cactoos/iterator/PagedTest.java
@@ -73,7 +73,7 @@ void containAllPagedContentInOrder() throws Exception {
                         return true;
                     },
                     new Matched<>(
-                        (x, y) -> x.equals(y),
+                        String::equals,
                         paged,
                         new IteratorOf<>("one", "two", "three", "four", "five")
                     )
@@ -101,8 +101,8 @@ void reportTotalPagedLength() {
         final Paged<String> paged = new Paged<>(
             pages.next(),
             page -> new Ternary<>(
-                () -> pages.hasNext(),
-                () -> pages.next(),
+                pages::hasNext,
+                pages::next,
                 () -> new IteratorOf<String>()
             ).value()
         );
@@ -128,8 +128,8 @@ void throwsNoSuchElement() {
                 () -> new Paged<>(
                     pages.next(),
                     page -> new Ternary<>(
-                        () -> pages.hasNext(),
-                        () -> pages.next(),
+                        pages::hasNext,
+                        pages::next,
                         () -> new IteratorOf<String>()
                     ).value()
                 ).next()
diff --git a/src/test/java/org/cactoos/list/NoNullsTest.java b/src/test/java/org/cactoos/list/NoNullsTest.java
index f007964c2..c6ce16269 100644
--- a/src/test/java/org/cactoos/list/NoNullsTest.java
+++ b/src/test/java/org/cactoos/list/NoNullsTest.java
@@ -135,7 +135,7 @@ void getThrowsErrorIfListIteratorPreviousValueIsNullValue() {
         list.set(0, null);
         new Assertion<>(
             "must throw error if previous value in iterator is null",
-            () -> listiterator.previous(),
+            listiterator::previous,
             new Throws<>(
                 "Previous item is NULL",
                 IllegalStateException.class
diff --git a/src/test/java/org/cactoos/proc/BiProcOfTest.java b/src/test/java/org/cactoos/proc/BiProcOfTest.java
index dd29ea176..df9bbd5a2 100644
--- a/src/test/java/org/cactoos/proc/BiProcOfTest.java
+++ b/src/test/java/org/cactoos/proc/BiProcOfTest.java
@@ -88,9 +88,7 @@ void worksWithProc() throws Exception {
             "Must execute BiProc with Proc",
             new BiProcOf<>(
                 new ProcOf<>(
-                    input -> {
-                        done.set(input);
-                    }
+                    done::set
                 )
             ),
             new Satisfies<>(
diff --git a/src/test/java/org/cactoos/proc/ProcOfTest.java b/src/test/java/org/cactoos/proc/ProcOfTest.java
index 7cd7bb137..66d813d9e 100644
--- a/src/test/java/org/cactoos/proc/ProcOfTest.java
+++ b/src/test/java/org/cactoos/proc/ProcOfTest.java
@@ -64,9 +64,7 @@ void worksWithLambda() throws Exception {
         new Assertion<>(
             "Must execute Proc with Lambda",
             new ProcOf<>(
-                input -> {
-                    done.set(input);
-                }
+                done::set
             ),
             new Satisfies<>(
                 proc -> {
diff --git a/src/test/java/org/cactoos/proc/RunnableOfTest.java b/src/test/java/org/cactoos/proc/RunnableOfTest.java
index d21ea260a..aea4dda5e 100644
--- a/src/test/java/org/cactoos/proc/RunnableOfTest.java
+++ b/src/test/java/org/cactoos/proc/RunnableOfTest.java
@@ -44,9 +44,7 @@ void convertsProcIntoRunnable() {
             "Must execute Runnable with Proc",
             new RunnableOf(
                 new ProcOf<>(
-                    input -> {
-                        done.set(input);
-                    }
+                    done::set
                 ),
                 obj
             ),
diff --git a/src/test/java/org/cactoos/scalar/FoldedTest.java b/src/test/java/org/cactoos/scalar/FoldedTest.java
index 17b20e3bd..0733d0feb 100644
--- a/src/test/java/org/cactoos/scalar/FoldedTest.java
+++ b/src/test/java/org/cactoos/scalar/FoldedTest.java
@@ -43,7 +43,7 @@ void skipIterable() throws Exception {
         new Assertion<>(
             "Must fold elements in iterable",
             new Folded<>(
-                0L, (first, second) -> first + second,
+                0L, Long::sum,
                 new HeadOf<>(
                     10,
                     new RangeOf<>(0L, Long.MAX_VALUE, value -> ++value)
diff --git a/src/test/java/org/cactoos/scalar/RepeatedTest.java b/src/test/java/org/cactoos/scalar/RepeatedTest.java
index d1869c4d4..7f7daf357 100644
--- a/src/test/java/org/cactoos/scalar/RepeatedTest.java
+++ b/src/test/java/org/cactoos/scalar/RepeatedTest.java
@@ -44,7 +44,7 @@ void runsMultipleTimes() throws Exception {
         new Assertion<>(
             "Must run scalar 3 times",
             new Repeated<>(
-                () -> atom.incrementAndGet(),
+                atom::incrementAndGet,
                 3
             ).value(),
             new IsEqual<>(3)
diff --git a/src/test/java/org/cactoos/scalar/ScalarOfTest.java b/src/test/java/org/cactoos/scalar/ScalarOfTest.java
index 4e470555e..aad17ee53 100644
--- a/src/test/java/org/cactoos/scalar/ScalarOfTest.java
+++ b/src/test/java/org/cactoos/scalar/ScalarOfTest.java
@@ -93,9 +93,7 @@ void worksWithProc() {
             "Must convert Proc into Scalar",
             new ScalarOf<>(
                 new ProcOf<>(
-                    input -> {
-                        done.set(input);
-                    }
+                    done::set
                 ),
                 ipt,
                 result