a b "K-12 (After School – Deluxe Edition) by Melanie Martinez on Apple Music". Apple Music. September 6, 2019 . Retrieved September 24, 2020.

Samways, Gemma (February 18, 2020). "Melanie Martinez review: Pop princess loses her way in fairytale settings". Evening Standard . Retrieved June 7, 2021. a b Caulfield, Keith (September 15, 2019). "Post Malone Scores Second No. 1 Album on Billboard 200 With 'Hollywood's Bleeding' ". Billboard . Retrieved September 16, 2019. a b "Top 100 México - Los más vendidos 2019" (in Spanish). Asociación Mexicana de Productores de Fonogramas y Videogramas. Archived from the original on January 25, 2020 . Retrieved January 25, 2020.K-12 CD/DVD Melanie Martinez". Melaniemartinez.com . Retrieved July 23, 2019. [ permanent dead link] An accompanying music film of the same name, written and directed by Melanie herself, made its cinema debut in Los Angeles on September 3rd and then in select cinemas worldwide on September 5th. It was later posted on YouTube. Melanie Martinez Announces 'The K-12 Tour' ". Live Nation Entertainment. July 29, 2019 . Retrieved August 13, 2019. Mūzikas Patēriņa Tops/ 37. nedēļa" (in Latvian). LAIPA. Archived from the original on October 10, 2019 . Retrieved November 27, 2019. Martinez, Melanie; Torvinen, Alissa (September 5, 2019), K-12 (Fantasy, Horror, Musical), Atlantic Records, Little Ugly , retrieved July 30, 2022

EESTI TIPP-40 MUUSIKAS: Ohhoo! Madison Mars ja Liis Lemsalu ründavad räpparite hirmuvalitsust!". Eesti Ekspress (in Estonian) . Retrieved September 18, 2019. Despite no singles being released prior to the album, K–12 debuted at number three on the US Billboard 200 with 57,000 album-equivalent units, of which 30,000 were pure album sales. It is Martinez's second US top-10 album [33] Additionally it topped the alternative album chart becoming her second consecutive top charter. Elsewhere the album reached the top 10 of eight different countries including the UK, Australia and Canada.Wass, Mike (November 30, 2015). "Melanie Martinez On Concept Albums & The Future Adventures Of Cry Baby: Idolator Interview". Idolator . Retrieved October 8, 2019. Wass, Mike (September 6, 2019). "Interview: Melanie Martinez On 'K-12' & Stepping Into Her Power". Idolator . Retrieved October 8, 2019. Selected items are only available for delivery via the Royal Mail 48® service and other items are available for delivery using this service for a charge. Wass, Mike (January 8, 2020). "Melanie Martinez Teases New EP, Which Is Probably Called 'After School' ". Idolator . Retrieved July 7, 2021. Gamboa, Glenn (May 23, 2019). "LI Sound: Melanie Martinez readying new album, movie". Newsday . Retrieved May 30, 2019.