Courses for learning RP:
https://receivedpronunciation.thinkific.com/collections
https://www.pinterest.com/mypronunciation/
Facebook groups:
https://www.facebook.com/groups/mypronunciation
https://www.facebook.com/groups/rpenglish
https://www.facebook.com/mypronunciation
Wikipedia materials:
https://en.wikipedia.org/wiki/International_Phonetic_Alphabet
https://en.wikipedia.org/wiki/Received_Pronunciation
https://en.wikipedia.org/wiki/General_American_English
https://en.wikipedia.org/wiki/Mid-Atlantic_accent
https://en.wikipedia.org/wiki/IPA_vowel_chart_with_audio
https://en.wikipedia.org/wiki/IPA_pulmonic_consonant_chart_with_audio
https://en.wikipedia.org/wiki/Stress_(linguistics)
https://en.wikipedia.org/wiki/Voice_(phonetics)
https://en.wikipedia.org/wiki/Glottal_stop
https://en.wikipedia.org/wiki/Glottalization
https://en.wikipedia.org/wiki/Airstream_mechanism
https://en.wikipedia.org/wiki/Intonation_(linguistics)
https://en.wikipedia.org/wiki/Tone_(linguistics)
https://en.wikipedia.org/wiki/Stress_(linguistics)
https://en.wikipedia.org/wiki/Vocal_resonation
https://en.wikipedia.org/wiki/Vocal_register
https://en.wikipedia.org/wiki/Vocal_cords
https://en.wikipedia.org/wiki/Elocution
https://en.wikipedia.org/wiki/Accent_reduction
https://en.wikipedia.org/wiki/English_phonology
https://en.wikipedia.org/wiki/Phonetics
https://en.wikipedia.org/wiki/Speech
https://en.wikipedia.org/wiki/Syllable
https://en.wikipedia.org/wiki/Linking_and_intrusive_R
https://en.wikipedia.org/wiki/Diphthong
https://en.wikipedia.org/wiki/Monophthong
https://en.wikipedia.org/wiki/Semivowel
https://en.wikipedia.org/wiki/Vowel_length
https://en.wikipedia.org/wiki/Velarization
https://en.wikipedia.org/wiki/Muscle_memory
https://en.wikipedia.org/wiki/Spaced_repetition
https://en.wikipedia.org/wiki/Behaviour_therapy
https://en.wikipedia.org/wiki/Feedback
https://en.wikipedia.org/wiki/Head_voice
https://en.wikipedia.org/wiki/Chest_voice
https://en.wikipedia.org/wiki/Isochrony
https://en.wikipedia.org/wiki/Prosody_(linguistics)
https://en.wikipedia.org/wiki/Manner_of_articulation
https://en.wikipedia.org/wiki/Nasalization
https://en.wikipedia.org/wiki/International_Phonetic_Alphabet
https://en.wikipedia.org/wiki/History_of_the_International_Phonetic_Alphabet
https://en.wikipedia.org/wiki/International_Phonetic_Association
https://en.wikipedia.org/wiki/Phonetics
https://en.wikipedia.org/wiki/Paul_Passy
https://en.wikipedia.org/wiki/Daniel_Jones_(phonetician)
https://en.wikipedia.org/wiki/Peter_Ladefoged
Rhotic vs Non-rhotic accents
https://www.thoughtco.com/rhoticity-speech-4065992
https://www.voicescienceworks.org/breath.html
What is Received Pronunciation? (Note that the definition can vary slightly.)
https://www.collinsdictionary.com/dictionary/english/received-pronunciation
https://dictionary.cambridge.org/dictionary/english/received-pronunciation
https://www.thefreedictionary.com/Received+Pronunciation
The Mid-Atlantic Accent (American equivalent of RP)
https://www.snopes.com/fact-check/mid-atlantic-accent/
https://www.urbandictionary.com/define.php?term=Mid-Atlantic%20accent
BBC English
http://www.bbc.co.uk/learningenglish/english/features/pronunciation/longvowel1
Received Pronunciation in the media:
https://www.bbc.com/future/article/20180307-what-does-your-accent-say-about-you
https://www.independent.co.uk/voices/accent-discrimination-work-job-prejudice-b1399561.html
https://www.dailymail.co.uk/tvshowbiz/article-8852721/Lily-Collins-wishes-English-accent.html
https://www.britishcouncil.org/voices-magazine/uk-accents-not-what-you-say-how-you-say-it
https://abagond.wordpress.com/2008/06/18/received-pronunciation/
http://www.classicbond.com/forum/viewtopic.php?t=2405
https://thecritic.co.uk/from-rp-to-cock-er-ney/
Regional accents are still a bar to law careers
"The researchers found that most people would prefer to be represented by a barrister with a posh voice and that lawyers hailing from beyond the home counties — Peake is from Bolton — sound less intelligent or professional."
"Researchers played recordings of a closing speech by the defence in a criminal trial delivered in received pronunciation (RP), the so-called Queen’s English, and in seven other accents. From 99 survey respondents, more than 80 per cent said they would be “comfortable” or “very comfortable” being represented by advocates with RP or southeastern accents."
Source: thetimes.co.uk
Miscellaneous links
https://teflpedia.com/Received_Pronunciation
https://wiki2.org/en/Conservative_Received_Pronunciation
https://www.bl.uk/british-accents-and-dialects/articles/received-pronunciation
https://airodyssey.net/reference/inflight/#doors
https://cuckoo.js.ila.titech.ac.jp/~yamagen/ling/ling-jones-single2021.pdf
https://www.receivedpronunciation.com/