^Miftari 2015,第32頁: "The center oriented and progressive UPyD" sfn模板錯誤: 無指向目標: CITEREFMiftari2015 (幫助)
^Lansford 2014,第1337頁: "Founded in 2007, the UPyD is a liberal, progressive party that advocates expanded federalism, including restoring central control over education and health care" sfn模板錯誤: 無指向目標: CITEREFLansford2014 (幫助)
^Sánchez-Cuenca & Dinas 2016,第144頁: "Unión Progreso y Democracia (UPyD– a progressive party in favour of the unity of Spain)" sfn模板錯誤: 無指向目標: CITEREFSánchez-CuencaDinas2016 (幫助)
^ 6.06.1Seoane Pérez 2010,第266頁: "The anti-nationalist, progressive UPyD failed to become the third political force, as some polls had predicted, but still won its first seat in the EP with 2.9 per cent of the vote" sfn模板錯誤: 無指向目標: CITEREFSeoane_Pérez2010 (幫助)
^Political Parties in Andalucia - UPyD. andalucia.com. [25 August 2015]. (原始内容存档于2021-05-03). Formed in 2007, the UPYD is a social liberal party that rejects nationalism in all forms and wants to adopt a system of symmetric federalism with political centralization as a territorial model
^ 8.08.1Mateos, Araceli; Penadés, Alberto. España: crisis y recortes(pdf). Revista de ciencia política (Santiago). 2013, 33 (1): 175 [January 12, 2016]. ISSN 0718-090X. (原始内容存档(PDF)于2016-03-08) (西班牙语). Unión Progreso y Democracia (5 escaños) es un partido de centro, con una combinación de ideología social liberal y de centralismo territorial, enemigo del nacionalismo periférico en España
^Painter 2013,第208頁: "The leftist ‘United Left’ and the moderate social liberal party Union, Progress and Democracy, saw their support increase by 3 per cent and 3.5 per cent, respectively" sfn模板錯誤: 無指向目標: CITEREFPainter2013 (幫助)
^Wolfram Nordsieck. SPAIN. Parties and Elections in Europe. [15 August 2015]. (原始内容存档于2018-10-23). Unión, Progreso y Democracia (UPD): Social liberalism
^ 12.012.112.2Ávila López 2015,第85頁: "Party: UPyD: Unión Progreso y Democracia (Union, Progress & Democracy). President / Leader: Andrés Herzog. Ideology: Centralism, secularism, European federalism" sfn模板錯誤: 無指向目標: CITEREFÁvila_López2015 (幫助)
^Dorange 2013,第100頁: "Partido españolista, republicano, nacional y laico, defiende la igualdad ciudadana en contra de los hechos diferenciales del nacionalismo considerados discriminatorios" sfn模板錯誤: 無指向目標: CITEREFDorange2013 (幫助)
^The Democratic Society. Union, Progress and Democracy (UPyD). demsoc.org. [3 Feb 2016]. (原始内容存档于2015-07-01). The party is rigidly secularist, and declares itself to be neither left nor right
^Vidal & Jiménez Losantos 2012: "cualquier acuerdo con UPyD, la única fuerza reformista española" sfn模板錯誤: 無指向目標: CITEREFVidalJiménez_Losantos2012 (幫助)
^The Democratic Society. Union, Progress and Democracy (UPyD). demsoc.org. [3 Feb 2016]. (原始内容存档于2015-07-01). The party is the most pro-European in Spain, and supports a federal Europe, which it sees as an important guarantor of individual rights
^How much is enough?. 经济学人. 6 November 2008 [9 June 2011]. (原始内容存档于2017-12-03). Mr Savater and Rosa Díez, a former Basque Socialist leader, have set up a new party of the radical centre called Union, Progress and Democracy (UPyD), in an effort to combine social liberalism with a defence of the idea of Spain
^Navarro, Pedro Antonio. El Congreso da su plácet al relevo(PDF). El siglo de Europa. No. 1068. 2014: 18 [3 Feb 2016]. ISSN 2254-9234. (原始内容(pdf)存档于2016-03-06) (西班牙语). Por su parte, UPyD, por boca de su jefa de filas, Rosa Díez, sorprendía en su intervención, no por el sentido de su pronunciamiento, que ya había sido anunciado con anterioridad, sino por la dureza de su exposición cuando aludía a la forma de Estado republicana, recurriendo a comparaciones como las de la República Popular de Corea o la República Islámica de Irán para denostar esta modalidad de Estado. Su confesión monárquica iba más allá, cuando dedicaba encendidos elogios a Juan Carlos I, de quien aseguró que “supo aprender de la sociedad española, aprender de fracasos y se puso del lado de los que queríamos construir una España plural y democrática”
^Rodríguez Teruel, Juan; Barrio, Astrid. Going National: Ciudadanos from Catalonia to Spain(pdf). South European Society and Politics (Routledge). 2016, 21 (4): 587–607 [2017-09-04]. ISSN 1360-8746. doi:10.1080/13608746.2015.1119646. (原始内容存档(PDF)于2018-06-18). In September 2007, Unión Progreso y Democracia had been created in Madrid. The new party had many similarities to Ciudadanos in terms of party agenda and strategy. It defended Spanish patriotism and criticised the evolution of decentralisation in Spain and the role of Catalan and Basque nationalism in Spanish politics
^Bonet i Martí 2015,第127頁: "Unión Progreso y Democracia (UPyD, a Spanish anti-nationalist party)" sfn模板錯誤: 無指向目標: CITEREFBonet_i_Martí2015 (幫助)
^Encyclopædia Britannica 2014,第488頁: "and Union, Progress and Democracy (UPD, 7.7%) on the centre-right" sfn模板錯誤: 無指向目標: CITEREFEncyclopædia_Britannica2014 (幫助)