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<!ATTLIST tab name CDATA #REQUIRED>

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<!ELEMENT li (#PCDATA | b)*>

<!ELEMENT p (#PCDATA | ul | b | i)* >

<!ELEMENT b (#PCDATA | ul | i)*>
<!ELEMENT i (#PCDATA | ul | b )* >
<!ELEMENT u (#PCDATA | b | i)* >

<!ELEMENT h1 (#PCDATA | b | i | u)* >
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