diff --git a/src/main/java/io/github/robwin/markup/builder/AbstractMarkupDocBuilder.java b/src/main/java/io/github/robwin/markup/builder/AbstractMarkupDocBuilder.java
index 4f926507..93a654bc 100644
--- a/src/main/java/io/github/robwin/markup/builder/AbstractMarkupDocBuilder.java
+++ b/src/main/java/io/github/robwin/markup/builder/AbstractMarkupDocBuilder.java
@@ -104,14 +104,26 @@ public abstract class AbstractMarkupDocBuilder implements MarkupDocBuilder {
     }
 
     @Override
-    public MarkupDocBuilder crossReference(String anchor) {
-        crossReference(anchor, null);
+    public MarkupDocBuilder anchor(String anchor, String text) {
+        documentBuilder.append(anchorAsString(anchor, text));
         return this;
     }
 
     @Override
-    public String crossReferenceAsString(String anchor) {
-        return crossReferenceAsString(anchor, null);
+    public MarkupDocBuilder crossReference(String anchor, String text) {
+        documentBuilder.append(crossReferenceAsString(anchor, text));
+        return this;
+    }
+
+    @Override
+    public MarkupDocBuilder crossReferenceTitle(String anchor, String text) {
+        documentBuilder.append(crossReferenceTitleAsString(anchor, text));
+        return this;
+    }
+
+    @Override
+    public String crossReferenceTitleAsString(String anchor, String text) {
+        return crossReferenceAsString(anchor, text);
     }
 
     @Override
diff --git a/src/main/java/io/github/robwin/markup/builder/MarkupDocBuilder.java b/src/main/java/io/github/robwin/markup/builder/MarkupDocBuilder.java
index 3f50910b..1883c993 100644
--- a/src/main/java/io/github/robwin/markup/builder/MarkupDocBuilder.java
+++ b/src/main/java/io/github/robwin/markup/builder/MarkupDocBuilder.java
@@ -60,21 +60,17 @@ public interface MarkupDocBuilder {
 
     MarkupDocBuilder tableWithColumnSpecs(List<MarkupTableColumn> columnSpecs, List<List<String>> cells);
 
-    MarkupDocBuilder anchor(String anchor);
+    MarkupDocBuilder anchor(String anchor, String text);
 
-    String anchorAsString(String anchor);
+    String anchorAsString(String anchor, String text);
 
-    /**
-     * @param anchor Target anchor
-     * @param text If not null, display this text instead of anchor
-     */
     MarkupDocBuilder crossReference(String anchor, String text);
 
     String crossReferenceAsString(String anchor, String text);
 
-    MarkupDocBuilder crossReference(String anchor);
+    MarkupDocBuilder crossReferenceTitle(String anchor, String text);
 
-    String crossReferenceAsString(String anchor);
+    String crossReferenceTitleAsString(String anchor, String text);
 
     MarkupDocBuilder newLine();
 
diff --git a/src/main/java/io/github/robwin/markup/builder/asciidoc/AsciiDocBuilder.java b/src/main/java/io/github/robwin/markup/builder/asciidoc/AsciiDocBuilder.java
index a1ff76d9..8db791c5 100644
--- a/src/main/java/io/github/robwin/markup/builder/asciidoc/AsciiDocBuilder.java
+++ b/src/main/java/io/github/robwin/markup/builder/asciidoc/AsciiDocBuilder.java
@@ -30,6 +30,7 @@ import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.regex.Pattern;
 
 import static org.apache.commons.lang3.StringUtils.*;
 
@@ -39,6 +40,10 @@ import static org.apache.commons.lang3.StringUtils.*;
 public class AsciiDocBuilder extends AbstractMarkupDocBuilder {
 
     private static final String ASCIIDOC_FILE_EXTENSION = "adoc";
+    private static final Pattern ANCHOR_FORBIDDEN_PATTERN = Pattern.compile("[^0-9a-zA-Z-_:.\\s]+");
+    private static final Pattern XREF_FORBIDDEN_PATTERN = Pattern.compile("[^0-9a-zA-Z-_:./#\\s]+");
+    private static final Pattern SPACE_PATTERN = Pattern.compile("[\\s]+");
+
 
     @Override
     public MarkupDocBuilder documentTitle(String title){
@@ -125,37 +130,46 @@ public class AsciiDocBuilder extends AbstractMarkupDocBuilder {
         return this;
     }
 
-    private static String normalizeReferenceAnchor(String anchor) {
-        return anchor.trim();
+    private static String normalizeAnchor(String anchor) {
+        return "_" + SPACE_PATTERN.matcher(ANCHOR_FORBIDDEN_PATTERN.matcher(anchor.trim()).replaceAll("")).replaceAll("_");
     }
 
     @Override
-    public MarkupDocBuilder anchor(String anchor) {
-        documentBuilder.append(anchorAsString(anchor));
-        return this;
-    }
-
-    @Override
-    public String anchorAsString(String anchor) {
+    public String anchorAsString(String anchor, String text) {
         StringBuilder stringBuilder = new StringBuilder();
-        stringBuilder.append(AsciiDoc.ANCHOR_START).append(normalizeReferenceAnchor(anchor)).append(AsciiDoc.ANCHOR_END);
+        if (text == null)
+            stringBuilder.append(AsciiDoc.ANCHOR_START).append(normalizeAnchor(anchor)).append(AsciiDoc.ANCHOR_END);
+        else
+            stringBuilder.append(AsciiDoc.ANCHOR_START).append(normalizeAnchor(anchor)).append(",").append(text).append(AsciiDoc.ANCHOR_END);
         return stringBuilder.toString();
     }
 
-    @Override
-    public MarkupDocBuilder crossReference(String anchor, String text) {
-        documentBuilder.append(crossReferenceAsString(anchor, text));
-        return this;
+
+    protected String normalizedCrossReferenceAsString(String anchor, String text) {
+        StringBuilder stringBuilder = new StringBuilder();
+        if (text == null)
+            stringBuilder.append(AsciiDoc.CROSS_REFERENCE_START).append(anchor).append(AsciiDoc.CROSS_REFERENCE_END);
+        else
+            stringBuilder.append(AsciiDoc.CROSS_REFERENCE_START).append(anchor).append(",").append(text).append(AsciiDoc.CROSS_REFERENCE_END);
+        return stringBuilder.toString();
+    }
+
+    private static String normalizeXRef(String anchor) {
+        return "_" + SPACE_PATTERN.matcher(XREF_FORBIDDEN_PATTERN.matcher(anchor.trim()).replaceAll("")).replaceAll("_");
     }
 
     @Override
     public String crossReferenceAsString(String anchor, String text) {
-        StringBuilder stringBuilder = new StringBuilder();
-        if (text == null)
-            stringBuilder.append(AsciiDoc.CROSS_REFERENCE_START).append(normalizeReferenceAnchor(anchor)).append(AsciiDoc.CROSS_REFERENCE_END);
-        else
-            stringBuilder.append(AsciiDoc.CROSS_REFERENCE_START).append(normalizeReferenceAnchor(anchor)).append(",").append(text).append(AsciiDoc.CROSS_REFERENCE_END);
-        return stringBuilder.toString();
+        return normalizedCrossReferenceAsString(normalizeXRef(anchor), text);
+    }
+
+    private static String normalizeTitleXRef(String anchor) {
+        return anchor.trim();
+    }
+
+    @Override
+    public String crossReferenceTitleAsString(String anchor, String text) {
+        return normalizedCrossReferenceAsString(normalizeTitleXRef(anchor), text);
     }
 
     private String escapeTableCell(String cell) {
diff --git a/src/main/java/io/github/robwin/markup/builder/markdown/MarkdownBuilder.java b/src/main/java/io/github/robwin/markup/builder/markdown/MarkdownBuilder.java
index 2fdc4e78..fa79fb94 100644
--- a/src/main/java/io/github/robwin/markup/builder/markdown/MarkdownBuilder.java
+++ b/src/main/java/io/github/robwin/markup/builder/markdown/MarkdownBuilder.java
@@ -23,8 +23,8 @@ import com.google.common.collect.Collections2;
 import io.github.robwin.markup.builder.AbstractMarkupDocBuilder;
 import io.github.robwin.markup.builder.MarkupDocBuilder;
 import io.github.robwin.markup.builder.MarkupTableColumn;
-import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.Validate;
 
 import java.io.IOException;
 import java.nio.charset.Charset;
@@ -157,24 +157,12 @@ public class MarkdownBuilder extends AbstractMarkupDocBuilder
     }
 
     @Override
-    public MarkupDocBuilder anchor(String anchor) {
-        documentBuilder.append(anchorAsString(anchor));
-        return this;
-    }
-
-    @Override
-    public String anchorAsString(String anchor) {
+    public String anchorAsString(String anchor, String text) {
         StringBuilder stringBuilder = new StringBuilder();
         stringBuilder.append("<a name=\"").append(normalizeReferenceAnchor(anchor)).append("\"></a>");
         return stringBuilder.toString();
     }
 
-    @Override
-    public MarkupDocBuilder crossReference(String anchor, String text) {
-        documentBuilder.append(crossReferenceAsString(anchor, text));
-        return this;
-    }
-
     @Override
     public String crossReferenceAsString(String anchor, String text) {
         StringBuilder stringBuilder = new StringBuilder();
@@ -190,8 +178,7 @@ public class MarkdownBuilder extends AbstractMarkupDocBuilder
 
     @Override
     public MarkupDocBuilder tableWithColumnSpecs(List<MarkupTableColumn> columnSpecs, List<List<String>> cells) {
-        if (CollectionUtils.isEmpty(columnSpecs))
-            throw new RuntimeException("Header is mandatory in Markdown");
+        Validate.notEmpty(columnSpecs);
 
         newLine();
         Collection<String> headerList = Collections2.transform(columnSpecs, new Function<MarkupTableColumn, String>() {