YES
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?xml-stylesheet type="text/xsl" href="cpfHTML.xsl"?>
<certificationProblem xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="cpf.xsd"><input><trsInput><trs><rules><rule><lhs><funapp><name>f</name><arg><funapp><name>a</name></funapp></arg><arg><funapp><name>f</name><arg><var>x</var></arg><arg><funapp><name>a</name></funapp></arg></funapp></arg></funapp></lhs><rhs><funapp><name>f</name><arg><funapp><name>a</name></funapp></arg><arg><funapp><name>f</name><arg><funapp><name>f</name><arg><funapp><name>a</name></funapp></arg><arg><funapp><name>a</name></funapp></arg></funapp></arg><arg><funapp><name>a</name></funapp></arg></funapp></arg></funapp></rhs></rule></rules></trs></trsInput></input><cpfVersion>2.1</cpfVersion><proof><crProof><compositionalPcps><trsC><rules /></trsC><trsP><rules /></trsP><joinSequences /><joinSequences /><relativeTerminationProof><rIsEmpty /></relativeTerminationProof><crProof><orthogonal /></crProof></compositionalPcps></crProof></proof><origin><proofOrigin><tool><name>Hakusan</name><version>0.10</version></tool></proofOrigin></origin></certificationProblem>