"ČNS IFPI" (in Czech). Hitparáda – Digital Top 100 Oficiální. IFPI Czech Republic. Note: Change the chart to CZ – SINGLES DIGITAL – TOP 100 and insert 20211 into search. Retrieved January 11, 2021.
"ČNS IFPI" (in Slovak). Hitparáda – Radio Top 100 Oficiálna. IFPI Czech Republic. Note: insert 202111 into search. Retrieved March 22, 2021.
"ČNS IFPI". IFPI ČR. Note: Select SK SINGLES DIGITAL TOP 100 and insert 20211 into search. Archived from the original on November 3, 2020. Retrieved March 8, 2021.
"ČNS IFPI". IFPI ČR. Note: Select SK SINGLES DIGITAL TOP 100 and insert 20211 into search. Archived from the original on November 3, 2020. Retrieved March 8, 2021.