diff --git a/index.xhtml b/index.xhtml
index 8e8d9b9..ab203a4 100644
--- a/index.xhtml
+++ b/index.xhtml
@@ -15,7 +15,7 @@
 </section>
 <section>
 	<p>
-		<strong>Artificial Intelligence</strong> (<abbr title="artificial intelligence">AI</abbr> is <ziba-link>intelligence</ziba-link> of <ziba-link>software</ziba-link> or a <ziba-link>machine</ziba-link>.
+		<strong>Artificial Intelligence</strong> (<abbr title="artificial intelligence">AI</abbr> is <a href="intelligence/">intelligence</a> of <a href="software/">software</a> or a <a href="machine/">machine</a>.
 	</p>
 </section>
 <section>
@@ -23,76 +23,76 @@
 	<section id="A">
 		<h2>A</h2>
 		<ul>
-			<li><ziba-link transform="lowercase">a-a testing</ziba-link></li>
-			<li><ziba-link transform="lowercase">a-b testing</ziba-link></li>
-			<li><ziba-link>activation function</ziba-link></li>
-			<li><ziba-link>artificial neural network</ziba-link></li>
+			<li><a href="a-a-testing/">a a testing</a></li>
+			<li><a href="a-b-testing/">a b testing</a></li>
+			<li><a href="activation-function/">activation-function</a></li>
+			<li><a href="artificial-neural-network/">artificial-neural-network</a></li>
 		</ul>
 	</section>
 	<section id="B">
 		<h2>B</h2>
 		<ul>
-			<li><ziba-link>back-propagation</ziba-link></li>
-			<li><ziba-link>bandit</ziba-link></li>
-			<li><ziba-link>bayes rule</ziba-link></li>
-			<li><ziba-link>bernoulli distribution</ziba-link></li>
-			<li><ziba-link>big data</ziba-link></li>
-			<li><ziba-link>binomial distribution</ziba-link></li>
-			<li><ziba-link>business intelligence</ziba-link></li>
+			<li><a href="back-propagation/">back-propagation</a></li>
+			<li><a href="bandit/">bandit</a></li>
+			<li><a href="bayes-rule/">bayes-rule</a></li>
+			<li><a href="bernoulli-distribution/">bernoulli-distribution</a></li>
+			<li><a href="big-data/">big-data</a></li>
+			<li><a href="binomial-distribution/">binomial-distribution</a></li>
+			<li><a href="business-intelligence/">business-intelligence</a></li>
 		</ul>
 	</section>
 	<section id="C">
 		<h2>C</h2>
 		<ul>
-			<li><ziba-link>central limit theorem</ziba-link></li>
-			<li><ziba-link>classification</ziba-link></li>
-			<li><ziba-link>clustering</ziba-link></li>
-			<li><ziba-link>computer vision</ziba-link></li>
-			<li><ziba-link>curse of dimensionality</ziba-link></li>
+			<li><a href="central-limit-theorem/">central-limit-theorem</a></li>
+			<li><a href="classification/">classification</a></li>
+			<li><a href="clustering/">clustering</a></li>
+			<li><a href="computer-vision/">computer-vision</a></li>
+			<li><a href="curse-of-dimensionality/">curse-of-dimensionality</a></li>
 		</ul>
 	</section>
 	<section id="D">
 		<h2>D</h2>
 		<ul>
-			<li><ziba-link>data</ziba-link></li>
-			<li><ziba-link>data engineer</ziba-link></li>
-			<li><ziba-link>data engineering</ziba-link></li>
-			<li><ziba-link>data science</ziba-link></li>
-			<li><ziba-link>data scientist</ziba-link></li>
-			<li><ziba-link>database</ziba-link></li>
-			<li><ziba-link>datum</ziba-link></li>
-			<li><ziba-link>decision tree</ziba-link></li>
-			<li><ziba-link>deep learning</ziba-link></li>
-			<li><ziba-link>dirichlet distribution</ziba-link></li>
+			<li><a href="data/">data</a></li>
+			<li><a href="data-engineer/">data-engineer</a></li>
+			<li><a href="data-engineering/">data-engineering</a></li>
+			<li><a href="data-science/">data-science</a></li>
+			<li><a href="data-scientist/">data-scientist</a></li>
+			<li><a href="database/">database</a></li>
+			<li><a href="datum/">datum</a></li>
+			<li><a href="decision-tree/">decision-tree</a></li>
+			<li><a href="deep-learning/">deep-learning</a></li>
+			<li><a href="dirichlet-distribution/">dirichlet-distribution</a></li>
 		</ul>
 	</section>
 	<section id="E">
 		<h2>E</h2>
 		<ul>
-			<li><ziba-link>empirical distribution</ziba-link></li>
-			<li><ziba-link>epsilon-greedy</ziba-link></li>
-			<li><ziba-link>evolutionary algorithm</ziba-link></li>
-			<li><ziba-link>exploitation</ziba-link></li>
-			<li><ziba-link>exploration</ziba-link></li>
-			<li><ziba-link>exponential distribution</ziba-link></li>
+			<li><a href="empirical-distribution/">empirical-distribution</a></li>
+			<li><a href="epsilon-greed/">epsilon-greedy</a></li>
+			<li><a href="evolutionary-algorithm/">evolutionary-algorithm</a></li>
+			<li><a href="exploitation/">exploitation</a></li>
+			<li><a href="exploration/">exploration</a></li>
+			<li><a href="exponential-distribution/">exponential-distribution</a></li>
 		</ul>
 	</section>
 	<section id="F">
 		<h2>F</h2>
 		<ul>
-			<li><ziba-link>feature</ziba-link></li>
-			<li><ziba-link>feature engineering</ziba-link></li>
-			<li><ziba-link>fraud detection</ziba-link></li>
+			<li><a href="feature/">feature</a></li>
+			<li><a href="feature-engineering/">feature-engineering</a></li>
+			<li><a href="fraud-detection/">fraud-detection</a></li>
 		</ul>
 	</section>
 	<section id="G">
 		<h2>G</h2>
 		<ul>
-			<li><ziba-link>gaussian distribution</ziba-link></li>
-			<li><ziba-link>gaussian process</ziba-link></li>
-			<li><ziba-link>genetic algorithm</ziba-link></li>
-			<li><ziba-link>gradient descent</ziba-link></li>
-			<li><ziba-link>ground truth</ziba-link></li>
+			<li><a href="gaussian-distribution/">gaussian-distribution</a></li>
+			<li><a href="gaussian-process/">gaussian-process</a></li>
+			<li><a href="genetic-algorithm/">genetic-algorithm</a></li>
+			<li><a href="gradient-descent/">gradient-descent</a></li>
+			<li><a href="ground-truth/">ground-truth</a></li>
 		</ul>
 	</section>
 	<section id="H">
@@ -101,7 +101,7 @@
 	<section id="I">
 		<h2>I</h2>
 		<ul>
-			<li><ziba-link>interval data</ziba-link></li>
+			<li><a href="interval-data/">interval-data</a></li>
 		</ul>
 	</section>
 	<section id="J">
@@ -110,110 +110,112 @@
 	<section id="K">
 		<h2>K</h2>
 		<ul>
-			<li><ziba-link>k-means</ziba-link></li>
+			<li><a href="k-means/">k-means</a></li>
 		</ul>
 	</section>
 	<section id="L">
 		<h2>L</h2>
 		<ul>
-			<li><ziba-link>law of large numbers</ziba-link></li>
-			<li><ziba-link>levels of measurement</ziba-link></li>
-			<li><ziba-link>likelihood</ziba-link></li>
-			<li><ziba-link>linear</ziba-link></li>
-			<li><ziba-link>linear regression</ziba-link></li>
-			<li><ziba-link>logistic function</ziba-link></li>
-			<li><ziba-link>logistic regression</ziba-link></li>
+			<li><a href="law-of-large-numbers/">law-of-large-numbers</a></li>
+			<li><a href="levels-of-measurement/">levels-of-measurement</a></li>
+			<li><a href="likelihood/">likelihood</a></li>
+			<li><a href="linear/">linear</a></li>
+			<li><a href="linear-regression/">linear-regression</a></li>
+			<li><a href="logistic-function/">logistic-function</a></li>
+			<li><a href="logistic-regression/">logistic-regression</a></li>
 		</ul>
 	</section>
 	<section id="M">
 		<h2>M</h2>
 		<ul>
-			<li><ziba-link>machine</ziba-link></li>
-			<li><ziba-link>machine learning</ziba-link></li>
-			<li><ziba-link>machine learning engineer</ziba-link></li>
-			<li><ziba-link>mean</ziba-link></li>
-			<li><ziba-link>monte carlo simulation</ziba-link></li>
-			<li><ziba-link>modeling</ziba-link></li>
-			<li><ziba-link>multi-armed bandit</ziba-link></li>
+			<li><a href="machine/">machine</a></li>
+			<li><a href="machine-learning/">machine-learning</a></li>
+			<li><a href="machine-learning-engineer/">machine-learning-engineer</a></li>
+			<li><a href="mean/">mean</a></li>
+			<li><a href="monte-carlo-simulation/">monte-carlo-simulation</a></li>
+			<li><a href="modeling/">modeling</a></li>
+			<li><a href="multi-armed-bandit/">multi-armed-bandit</a></li>
 		</ul>
 	</section>
 	<section id="N">
 		<h2>N</h2>
 		<ul>
-			<li><ziba-link>naive bayes</ziba-link></li>
-			<li><ziba-link>natural language processing</ziba-link></li>
-			<li><ziba-link>nominal data</ziba-link></li>
-			<li><ziba-link>non-linear</ziba-link></li>
+			<li><a href="naive-bayes/">naive-bayes</a></li>
+			<li><a href="natural-language-processing/">natural-language-processing</a></li>
+			<li><a href="nominal-data/">nominal-data</a></li>
+			<li><a href="non-linear/">non-linear</a></li>
 		</ul>
 	</section>
 	<section id="O">
 		<h2>O</h2>
 		<ul>
-			<li><ziba-link>online advertising</ziba-link></li>
-			<li><ziba-link>optical character recognition</ziba-link></li>
-			<li><ziba-link>ordinal data</ziba-link></li>
+			<li><a href="online-advertising/">online-advertising</a></li>
+			<li><a href="optical-character-recognition/">optical-character-recognition</a></li>
+			<li><a href="ordinal-data/">ordinal-data</a></li>
 		</ul>
 	</section>
 	<section id="P">
 		<h2>P</h2>
 		<ul>
-			<li><ziba-link>pareto distribution</ziba-link></li>
-			<li><ziba-link>porter stemmer</ziba-link></li>
-			<li><ziba-link>posterior</ziba-link></li>
-			<li><ziba-link>principal component analysis</ziba-link></li>
-			<li><ziba-link>prior</ziba-link></li>
-			<li><ziba-link>python programming language</ziba-link></li>
+			<li><a href="pareto-distribution/">pareto-distribution</a></li>
+			<li><a href="porter-stemmer/">porter-stemmer</a></li>
+			<li><a href="posterior/">posterior</a></li>
+			<li><a href="principal-component-analysis/">principal-component-analysis</a></li>
+			<li><a href="prior/">prior</a></li>
+			<li><a href="python-programming-language/">python-programming-language</a></li>
 		</ul>
 	</section>
 	<section id="Q">
 		<h2>Q</h2>
 		<ul>
-			<li><ziba-link>q-learning</ziba-link></li>
-			<li><ziba-link>qualitative data</ziba-link></li>
-			<li><ziba-link>quantitative data</ziba-link></li>
+			<li><a href="q-learning/">q-learning</a></li>
+			<li><a href="qualitative-data/">qualitative-data</a></li>
+			<li><a href="quantitative-data/">quantitative-data</a></li>
+			<li><a href="qualitative-research/">qualitative-research</a></li>
+			<li><a href="quantitative-research/">quantitative-research</a></li>
 		</ul>
 	</section>
 	<section id="R">
 		<h2>R</h2>
 		<ul>
-			<li><ziba-link>r programming language</ziba-link></li>
-			<li><ziba-link>random forest</ziba-link></li>
-			<li><ziba-link>ratio data</ziba-link></li>
-			<li><ziba-link>recurrent neural network</ziba-link></li>
-			<li><ziba-link>regression</ziba-link></li>
-			<li><ziba-link>reinforcement learning</ziba-link></li>
+			<li><a href="r-programming-language/">r-programming-language</a></li>
+			<li><a href="random-forest/">random-forest</a></li>
+			<li><a href="ratio-data/">ratio-data</a></li>
+			<li><a href="recurrent-neural-network/">recurrent-neural-network</a></li>
+			<li><a href="regression/">regression</a></li>
+			<li><a href="reinforcement-learning/">reinforcement-learning</a></li>
 		</ul>
 	</section>
 	<section id="S">
 		<h2>S</h2>
 		<ul>
-			<li><ziba-link>softmax</ziba-link></li>
-			<li><ziba-link>software</ziba-link></li>
-			<li><ziba-link>sql</ziba-link></li>
-			<li><ziba-link>stemming</ziba-link></li>
-			<li><ziba-link>supervised learning</ziba-link></li>
-			<li><ziba-link>support vector machine</ziba-link></li>
+			<li><a href="softmax/">softmax</a></li>
+			<li><a href="software/">software</a></li>
+			<li><a href="sql/">sql</a></li>
+			<li><a href="stemming/">stemming</a></li>
+			<li><a href="supervised-learning/">supervised-learning</a></li>
+			<li><a href="support-vector-machine/">support-vector-machine</a></li>
 		</ul>
 	</section>
 	<section id="T">
 		<h2>T</h2>
 		<ul>
-			<li><ziba-link>time series</ziba-link></li>
-			<li><ziba-link>training</ziba-link></li>
+			<li><a href="time-series/">time-series</a></li>
+			<li><a href="training/">training</a></li>
 		</ul>
 	</section>
 	<section id="U">
 		<h2>U</h2>
 		<ul>
-			<li><ziba-link>unsupervised learning</ziba-link></li>
+			<li><a href="unsupervised-learning/">unsupervised-learning</a></li>
 		</ul>
 	</section>
 	<section id="V">
 		<h2>V</h2>
 		<ul>
-			<li><ziba-link>variance</ziba-link></li>
-			<li><ziba-link>vector</ziba-link></li>
-			<li><ziba-link>visualization</ziba-link></li>
+			<li><a href="variance/">variance</a></li>
+			<li><a href="vector/">vector</a></li>
+			<li><a href="visualization/">visualization</a></li>
 		</ul>
 	</section>
 	<section id="W">