Anonymous

<?xml version="1.0" encoding="utf-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
	<xsd:element name="courses">
		<xsd:complexType>
			<xsd:sequence>
				<xsd:element name="course" maxOccurs="unbounded">
					<xsd:complexType>
						<xsd:sequence>
							
							<xsd:element name="professor" maxOccurs="unbounded"></xsd:element>
							
							<xsd:element name="books" maxOccurs="1">
								<xsd:complexType>
									<xsd:sequence>
										<xsd:element name="book" maxOccurs="unbounded">
											<xsd:complexType>
												<xsd:sequence>
													<xsd:element name="library" minOccurs="1"></xsd:element>
													<xsd:element name="notes"></xsd:element>
													<xsd:element name="title" maxOccurs="unbounded"></xsd:element>
													<xsd:element name="author" maxOccurs="unbounded"></xsd:element>
													<xsd:element name="call"></xsd:element>
												</xsd:sequence>
											</xsd:complexType>
										</xsd:element>
									</xsd:sequence>
								</xsd:complexType>
							</xsd:element>
							
						</xsd:sequence>
					</xsd:complexType>
				</xsd:element>
			</xsd:sequence>
		</xsd:complexType>
	</xsd:element>
</xsd:schema>

<courses>		
	<course>
		<professor></professor>
		<books>
			<book>
				<library></library>
				<notes></notes>
				<title></title>
				<author></author>
				<call></call>
			</book>
			<book>
				<library></library>
				<notes></notes>
				<title></title>
				<author></author>
				<call></call>
			</book>
		</books>
	</course>
	<course>
		<professor></professor>
		<books>
			<book>
				<library></library>
				<notes></notes>
				<title></title>
				<author></author>
				<call></call>
			</book>
		</books>
	</course>
	<course>
		<professor></professor>
		<books>
			<book>
				<library></library>
				<notes></notes>
				<title></title>
				<author></author>
				<call></call>
			</book>
		</books>
	</course>
</courses>