Xml Dtd File Error

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Hello!

Here is a Product Catalog Xml File, that I would like to Validate. In the site https://validator.w3.org/feed/check.cgi, I placed the File to be checked and got this following lines as response. This feed does not validate.
line 3, column 0: Undefined root element: catalog

Here I place the beginning and the end of the file, may someone can clear me some points to be fix.

<blockquote><?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE product_catalog SYSTEM "http://www.jdoqocy.com/content/dtd/product_catalog_1_1.dtd">
<catalog>
<product>
<programname>Fashionesta.com</programname>
<programurl>http://www.fashionesta.com?aff=cjcom</programurl>
<catalogname>Productfeed Master EN / USD</catalogname>
<lastupdated>2017-03-20 09:01:30.22</lastupdated>
<name>Dolce & Gabbana blouse</name>
<keywords>Dolce & Gabbana, Cotton, Elastane, dark blue</keywords>
<description>Timeless Dolce & Gabbana shirt.</description>
<sku>F-01-Bl-40751</sku>
<manufacturer>Dolce & Gabbana</manufacturer>
<upc>4251258516386</upc>
<currency>USD</currency>
<price>69</price>
<retailprice>249</retailprice>
<buyurl>http://www.jdoqocy.com/click-6XXXXX6-10963542?url=http%3A%2F%2Fwww.fashionesta.com%2Fus%2Ftimeless-dolce-and-gabbana-shirt-5.html</buyurl>
<impressionurl>http://www.ftjcfx.com/image-7565506-10963542</impressionurl>
<imageurl>http://images.fashionesta.eu/productimages/export_big/40751_1.jpg</imageurl>
<advertisercategory>Women > blouse</advertisercategory>
<instock>yes</instock>
<standardshippingcost>16.57</standardshippingcost>
</product>
<product>
<programname>Fashionesta.com</programname>
<programurl>http://www.fashionesta.com?aff=cjcom</programurl>
<catalogname>Productfeed Master EN / USD</catalogname>
<lastupdated>2017-03-20 09:01:30.438</lastupdated>
<name>Carrera sunglasses</name>
<keywords>Carrera, Metal, purple</keywords>
<description>Carrera. 100% Metal.</description>
<sku>U-83-So-43547</sku>
<manufacturer>Carrera</manufacturer>
<upc>4251258525562</upc>
<currency>USD</currency>
<price>59</price>
<retailprice>129</retailprice>
<buyurl>http://www.dpbolvw.net/click-6XXXXX6-10963542?url=http%3A%2F%2Fwww.fashionesta.com%2Fus%2Fcarrera-11.html</buyurl>
<impressionurl>http://www.ftjcfx.com/image-7565506-10963542</impressionurl>
<imageurl>http://images.fashionesta.eu/productimages/export_big/43547_1.jpg</imageurl>
<advertisercategory>Unisex > sunglasses</advertisercategory>
<instock>yes</instock>
<standardshippingcost>16.57</standardshippingcost>
</product>
</catalog></blockquote>

Thank You and Warm regards!
LFABIO