<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
       <xs:element name="observation">
              <xs:complexType>
                     <xs:sequence>
                            <xs:element name="header">
                                   <xs:complexType>
                                          <xs:sequence>
                                                 <xs:element name="version" type="xs:double"></xs:element>
                                                 <xs:element name="road-station" type="xs:string"></xs:element>
                                                 <xs:element name="filetype" type="xs:string"></xs:element>
                                             </xs:sequence>
                                      </xs:complexType>
                               </xs:element>
                            <xs:element name="measure-list">
                                   <xs:complexType>
                                          <xs:sequence>
                                                 <xs:element name="measure" maxOccurs="unbounded">
                                                        <xs:complexType>
                                                               <xs:sequence>
                                                                      <xs:element name="observation-time" type="xs:string"></xs:element>
                                                                      <!-- observation-time = Date in UTC ISO8601 -->
                                                                      <xs:element name="at" type="xs:double"></xs:element>
                                                                      <!-- at = Air Temperature 2m degree Celsius -->
                                                                      <xs:element name="td" type="xs:double"></xs:element>
                                                                      <!-- td = Dew Point Temperature 2m degree Celsius-->
                                                                      <xs:element name="st" type="xs:double"></xs:element>
                                                                      <!-- st = Road Surface Temperature degree Celsius -->
                                                                  </xs:sequence>
                                                           </xs:complexType>
                                                    </xs:element>
                                             </xs:sequence>
                                      </xs:complexType>
                               </xs:element>
                        </xs:sequence>
                 </xs:complexType>
          </xs:element>
   </xs:schema>