diff --git a/src/procedures.php b/src/procedures.php
deleted file mode 100644
index 645a731..0000000
--- a/src/procedures.php
+++ /dev/null
@@ -1,272 +0,0 @@
-<?php
-
-// Microdata Extractor
-function extractMicrodata(DOMNodeList $topLevelItems)
-{
-    // Step 1
-    $result = new stdClass;
-
-    // Step 2
-    $items = [];
-
-    // Step 3
-    // items = map("top-level microdata items", item => getObject(item))
-    $items = array_map('getObject', iterator_to_array($topLevelItems));
-
-    /*foreach ($topLevelItems as $topLevelItem) {
-        $items[] = getObject($topLevelItem);
-    }*/
-
-    // Step 4
-    $result->items = $items;
-
-    // Step 5
-    return $result;
-}
-
-
-// Get Object
-
-function getObject(DOMElement $item, $memory = [])
-{
-    // Step 1
-    $result = new stdClass();
-
-    // Step 2 in 2nd parameter of this function
-    // $memory = [];
-
-    // Step 3
-    $memory[] = $item;
-
-    // Step 4
-    $itemtype = $item->getAttribute('itemtype');
-    $result->type = $itemtype ? preg_split('/\s+/', $itemtype) : [];
-    // @todo Check if types are valid absolute urls
-
-    // Step 5
-    if ($itemId = $item->getAttribute('itemid')) {
-        $result->id = $itemId;
-    }
-    // @todo Check if item ids are valid absolute urls or like isbn:xxx
-
-    // Step 6
-    $properties = new stdClass;
-
-    // Step 7
-    foreach (getProperties($item) as $element) {
-        $value = getPropertyValue($element);
-
-        if (isItem($value)) {
-            foreach ($memory as $memory_item) {
-                if ($element->isSameNode($memory_item)) {
-                    $value = 'ERROR';
-                }
-            }
-
-            if ($value != 'ERROR') {
-                $value = getObject($value, $memory);
-            }
-        }
-
-        foreach (getPropertyNames($element) as $name) {
-            $properties->{$name}[] = $value;
-        }
-    }
-
-    // Step 8
-    $result->properties = $properties;
-
-    // Step 9
-    return $result;
-}
-
-// https://www.w3.org/TR/microdata/#dfn-property-name
-function getPropertyNames(DOMElement $item)
-{
-    // Step 1
-    $itemprop = $item->getAttribute('itemprop');
-    $tokens = $itemprop ? preg_split('/\s+/', $itemprop) : [];
-
-    // Step 2
-    $properties = [];
-
-    // Step 3
-    foreach ($tokens as $token) {
-        if (isAbsoluteUri($token)) {
-            $properties[] = $token;
-        } elseif (isTypedItem($item)) {
-            $properties[] = /*$vocabularyIdentifier . */ $token;
-        } else {
-            $properties[] = $token;
-        }
-    }
-
-    $properties = array_unique($properties);
-
-    return $properties;
-}
-
-// https://www.w3.org/TR/microdata/#dfn-item-properties
-function getProperties(DOMElement $root)
-{
-    // Step 1
-    $results = [];
-    $memory = [];
-    $pending = [];
-
-    // Step 2
-    $memory[] = $root;
-
-    // Step 3
-    if ($root->hasChildNodes()) {
-        $childNodes = iterator_to_array($root->childNodes);
-
-        $childNodes = array_filter($childNodes, function ($node) {
-            return $node instanceof DOMElement;
-        }); // Get only DOMElements
-
-        $pending = array_merge($pending, $childNodes);
-    }
-
-    // Step 4
-    if ($root->hasAttribute('itemref')) {
-        $tokens = preg_split('/\s+/', $root->getAttribute('itemref'));
-
-        foreach ($tokens as $token) {
-            // @todo Implement xpath query and get the first item
-        }
-    }
-
-    // Step 5
-    while ($pending) {
-        // Step 6
-        $current = array_pop($pending);
-
-        // Step 7
-        // in_array can't compare objects
-        /*if (in_array($current, $memory)) {
-            // There is MicrodataError
-            continue;
-        }*/
-        $error = false;
-
-        foreach ($memory as $memory_item) {
-            if ($current->isSameNode($memory_item)) {
-                // There is MicrodataError
-                $error = true;
-                break;
-            }
-        }
-
-        if ($error) {
-            continue;
-        }
-
-        // Step 8
-        $memory[] = $current;
-
-        // Step 9
-        if (! $current->hasAttribute('itemscope')) {
-            if ($current->hasChildNodes()) {
-                $childNodes = iterator_to_array($current->childNodes);
-
-                $childNodes = array_filter($childNodes, function ($node) {
-                    return $node instanceof DOMElement;
-                });
-
-                $pending = array_merge($pending, $childNodes);
-            }
-        }
-
-        // Step 10
-        if ($current->hasAttribute('itemprop') && /* hasPropertyNames */ getPropertyNames($current)) {
-            $results[] = $current;
-        }
-
-        // Step 11: Return to loop
-    }
-
-    // Step 12: End of loop. Sort results in tree order.
-
-    $results = array_reverse($results);
-
-    // Step 13
-    return $results;
-}
-
-// https://www.w3.org/TR/microdata/#dfn-property-value
-function getPropertyValue(DOMElement $item)
-{
-
-    if ($item->hasAttribute('itemscope')) {
-        return $item;
-    }
-
-    if ($item->hasAttribute('content')) {
-        return $item->getAttribute('content');
-    }
-
-    $base = $item->ownerDocument->documentURI;
-
-    switch ($item->tagName) {
-        case 'audio':
-        case 'embed':
-        case 'iframe':
-        case 'img':
-        case 'source':
-        case 'track':
-        case 'video':
-            if ($item->hasAttribute('src')) {
-                $result = $item->getAttribute('src');
-
-                // @todo check against protocol relative urls like "//example.com/test.jpg"
-                return isAbsoluteUri($result) ? $result : $base.$result;
-            }
-        case 'a':
-        case 'area':
-        case 'link':
-            if ($item->hasAttribute('href')) {
-                $result = $item->getAttribute('href');
-
-                return isAbsoluteUri($result) ? $result : $base.$result;
-            }
-        case 'object':
-            if ($item->hasAttribute('data')) {
-                $result = $item->getAttribute('data');
-
-                return isAbsoluteUri($result) ? $result : $base.$result;
-            }
-        case 'data':
-        case 'meter':
-            if ($item->hasAttribute('value')) {
-                return $item->getAttribute('value');
-            }
-        case 'time':
-            if ($item->hasAttribute('datetime')) {
-                return $item->getAttribute('datetime');
-            }
-        default:
-            return $item->textContent;
-    }
-}
-
-function isItem($element)
-{
-    return $element instanceof DOMElement && $element->hasAttribute('itemscope');
-}
-
-function isTypedItem(DOMElement $item)
-{
-    $tokens = [];
-
-    if ($item->hasAttribute('itemtype')) {
-        $tokens = preg_split("/\s+/", $item->getAttribute('itemtype'));
-    }
-
-    return !empty($tokens);
-}
-
-function isAbsoluteUri(string $uri)
-{
-    return preg_match("/^\w+:/", trim($uri));
-}