CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="120"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "publications.waset.org",cType: 'non-interactive',cRay: '913590189890ce11',cH: 'D.OkHthfp6F4nDMkFZx64bQaDkfS27zPmYDdhN_OB5o-1739793058-1.2.1.1-finIvJ.oFQV7PQioAD3agFAxw9jMkmryAI7opQxNiomMuZ6RyF13OxtyWW6tfFzf',cUPMDTk: "\/abstracts\/search?q=price%20control&page=10&__cf_chl_tk=hFPQh5gIlJVNJNxuqZWudBzzwhYzpT.gMvJHkptOtQw-1739793058-1.0.1.1-ysJK5TQpgVrJl9__QoY1unB2KR4VHGhIp4.qCJ9I8NM",cFPWv: 'b',cITimeS: '1739793058',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/abstracts\/search?q=price%20control&page=10&__cf_chl_f_tk=hFPQh5gIlJVNJNxuqZWudBzzwhYzpT.gMvJHkptOtQw-1739793058-1.0.1.1-ysJK5TQpgVrJl9__QoY1unB2KR4VHGhIp4.qCJ9I8NM",md: "Ou95psA3OFTTfd5VAWD_lzCRdyWpv5xKzlwvm3ApumQ-1739793058-1.2.1.1-3gDKN6nhzyVZxjJflHUVk2wUH92_fMq7bO1045OhrCCGJgQsMkEqdvioazrr.CKKFo.OB_rBPoL.m00qHWTt9QAuMTqJecw3RHRAql_E5GjcsaOhV2Jl2qHytSME3g6uLKF7nRH9G2UsjGj0SfH_Xn5hBhCuUduiXyjHX84D8y04xv5lkypPN_7jiNYAtgb3VE_7PArD9e_llZ_ICVbR20RYVe8uh.D6b8rJr8PFdJyi0RLQ1znX.74BCOhusmlEZH9VFTG4xCrlwbRfd4IkFGga0OaIYAihm.6mQCRTqv6ek37ODgSBtYN9GDAUt00nxwAxRKd6s8GKSwwXYrQvdJSUUL9T4YbgZNQ9Z9UitFOMzbaUiRhMp80I8F2ed16y3i2fD1HnOLXrNuc2OEQ1Uyb1aLIOrdtuC3G4XWSzMn13H.pgiDelfcfPc1xXtqZEC7Ha3C5kdEU_v5uDVw8PeyAxpQpzzLbj67NNELmxzAuWIbtsG7ovM15NU2Aw8GlpqCBbA4GAN_TZ8tQAhG6FFXF1i1VmddDGZpS7O2Cm3rIroffxuScAV.faDf1a2Um2rfj9ai6BWDimi2McEmePLQTOOHCY_fFrE.cHPjCk8_gHO7N0B0RL8sbFsTT3pbPUx4Y5uwJOiDI3qgpiVPjkDtigSwlJDlht9UkFzpzK.Qc2MMc4IGg0B4s22BLQx_Jip5TssVvLeAYdDFndcrkAyRfirNSQKCDjuOzVbTirRYmRSgfBQ4LNvkMGPEh_jS62kj24B5ap0CvGxTyYQ5OQApa7lfLOgA3XiaoKQm38Az17Vy5rAIgoLeFB3cTBE0vf_AP1GzHvJmJBVB7Jyi25ZbgHjs3a0TzIDA9MmljM93_Gw4SCE3cbxIzT8knGYKg7ceriyqKD6435Qc_wIXgzrBOaUzLvEzhRWLa1gSNMNuws8cWfLctPg6.Wpd_nYy3GzI43jKGduGk3v6bDAmXesByJZfPL5icH8HSYTgpt_k0spA1eK1sffPkcWtaFPIasiX3hoFdX_3OuBzlIbs3UgvUHmg2q0pcI.53NsYlF3_.0ml4S.L7jOkPvyGxWrJ_P63h3tnO.JhF.WLnj23X1wg0tc89KA7xLCg3OzofdTy2.10I4wqyYY1iXqsHE_095bBi5gThjNS8y9ZbarJA7D7Pc0yol8grykgk7LiD7mTqEW4YKov3K8ZtEwKNgrl0Ch6NCwRP.aqcEi9hbGzP5gFsvc1YGIU3.UQAMKNFejircVp1uOE6_Unv7TihYtjHJunBfB.SGd7nA8fca_gjVbkK7qlnuT4pxDSg.7fFKvfYLX7hBgpBaM7l3FztQBIjT09K5STsgMbx7WUSN.4J7OViocwaAQwkj5Ym1oEy9_Y0kXDCe7LGjACoAQpdhApUpqqt8D2ON5bWs5_mQBGRXvYEYyEsq3BI.tcKstVPEPyQ54MN10LinlDffL4lcxDGFMrB7.i5fU4B4uQqDXJ5lk0Sz4PCeRJLCHM6HuHt4T9HDwM.Iruu4tXChj3SYgaj0dwEsOHQjMYMix6bVpHyerN0NAtFtH28JAeaQUAL4J.sldKp4LUc4g1L_O0XsPT3p5YS.ix6nFIslNNY8KwupHEFu9IIxXtItrXCVXKMOR6xbxRXL3nAf_RukBmJJJrkwdZxAgyyEx5I1XI1lx52AF5Cb2qvPWuTADyiH3gilwdqI9pXFV0cQcArS.wQS2Nfs284CMpc7AvSViG7r3lHIKuUyKi8zoQB8XPdzLTue7Hw6fNCFo_WhjhB2_gb2nv413PuXB6hD_SRAEMNxgxAZ3qWuYAtjx8IcPJoJT4SllA73b_kEVaTfysxdVMFSnIBY34ShlFI9KubG0FQXQVQ8PISSUQB1D0oC5Fg416NVtgnI7x7ojPwmFGaJoRo8DI90fEbNmOFLOzHSDBSXF3VA7XB8oYi8p20kLPdB2tTch22z9PM7wB3ePdmcsbV9eBFT",mdrd: "zQ8PQENIfIrSlb..1PWBnxPjkHp59kQswz0brs5rcfo-1739793058-1.2.1.1-8JN_VuTkWN0HiFaGbBPtfdKiuSkZ3REFA9mLUCCYzL2g8pKTLrGaGhQjHntmgG8cEk1Ajn5x2b3fYXzoCOPE0VhzxeXVPxhOyXM2C6BdatatC4LYtiW2QSvK0x8ISSUC03u05.h.LEkxWAsEPp8XeSt2cY4.8QRICUUJ5g8pWTYGw3CJIrRwBKK3QVDoTLOCoQxcp05dby162VJmZFtE9Jnrf25iRadwAC6J6HCYGy9gHI9K_M68qoav9PDvBLKYN56q8oxs2XZ7O1GlGYVIeDFIYXPkLv66wNRqIO8MXPw4LEwJmBPf2oQRvhayVDSWmnkS5tGmqGkz7IFxWj8Qtm5W3mxsYGKuronLFH24_Ad0u138S8tQC9CAa235ZbNzsSOxSRjrKU_gi6xyTpaFn7ZfA45yq6FcGWyEQC6gYLH8pPDIcb7N.U1ylK2jbmILt51bKwkznn2XGKGHnMZWmUH0KvDkwrDet8DBnBR4Qztb4W00L2RIt33uUbq6s10cdrYWSjI3sssCIEnzwdITqj5Cmgd_WyGaRkwUMkjs6aMBZR4CA1L8SQGb6AFuSDf64bbftyM6JQJxi4kY8rhFHwxym5oNvcnfH4r1NJ26iHl5C6hHCHH0dR2qpbrbFUZwCwiLUNaitQjt8xG2zywUo6xX.PZCpMaKJren1APTS1HJOF_qd0xVV.f3yXYu_NDtf_IyoXQLWyLpi5RGuBXoOX.G1qWzQxoCnqmhQvbmre4Ay5Bvsygg3RyD9EQQn8um5awq3gkx_lxpw5JaIXPFn7eZKJY_tMJKE19Xn_gMVEleb83vH4pHPVm9l5yhYthnO9tvfZzPtdHnFIgEpZDYzcV9MgXsu2BIrulxx_CVWM5QhuiW_NBOS54U7JVdVBbwZmSsdxTSSYplFWG3TC.4_7vUtZnWBVYJ8Kea79vS10KH6gnyQ7EJu65OY4DEHjcYsioZ5izdyMly2QV2WoO_MjhSDZ03YbfliR..89_PuHyTNCnuFbC5ChMd_gvZninwq8SayiWS5FgWG3o_Nnp_YPBoySCTsqvR7HrMHGwuW8TQ2zgx5AKEOLpcxkDAkLqCKCkEEdPuKMr20.y_PeKOksVIwIhTiRyIw3EcN1Q.IXnf8r1IAJMHl4qW0.f3WNyQDVv7yGJupvgAAkVGeN50Hdr7j_0_BCbBmQ1JH.eE_uIERZAH5pQIbLI1iIWBDvrtbpGTqyiR.hqD4xFwzZIczDZDY22pF5f079iykWyHmoTIQbS7AaDeomv_RFp8JvZ0nj92I3EdGWkxBryzVTAEpeGAZMKJg6tbVLtPeUdjPDoulZiYSVu1Slr4yGHetmJdc2IIyiOUwhpymK2DCYqlMeyXEWXdi6AoiQCL4VdS6wEZpxzsX9BjEAB5oP4oWUTenL2qhYucsdTyr3ZkjJFSIUpgdttmY4dsHVy0e1kEPuZTHWqVC.5xp6PinAQx32_E1wmvUJcviZ.Q3Ln0pkxC8GLY4GlF4mgu8BtJBmcvvVTczSP5gLH8cqTfWXJxUu468ioRB5vz_3TP9C.Yni0.oIe8tVtbwAxqs6t.6xRwDY3C9e1afkQq5vof2OhrXhjEvWX1V4RJ9mXY.xel2eLswMs_uUCbp77hsXJen7pJ75wYoIaXNCbKgTgWhv3Z_AefF4VCIiku1hp7t3XomGpcItWqYv18zIAVj2tXheY.AoGfboIiCCNZchkNaUSHQ9kA0I4RgxxHVjD_t8p_9o9WJ8rxkMqTFve999ETIfrovGG1.F481AWAKX_GwMKRmdblWdLklc4DXETa2sBW88LDjLsiNLd_cZLR3vjL3.jn.87klBocEp1hCpgWe32ShnDVligru5ez9fKnEGB4SllxXrsh0EyV_qNJwLwe0XDHA1s8cwYyt2nNHyMiTXqozQInbdPMazV8GQtYgj3DU0xnjKYbYdf0UFO3LdaljErNZoIVjNYDa7Wx1wL65zXhCU5I7KG4wnncESXe1o7ni3xdtg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=913590189890ce11';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/abstracts\/search?q=price%20control&page=10&__cf_chl_rt_tk=hFPQh5gIlJVNJNxuqZWudBzzwhYzpT.gMvJHkptOtQw-1739793058-1.0.1.1-ysJK5TQpgVrJl9__QoY1unB2KR4VHGhIp4.qCJ9I8NM" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>