There were seven elements (with Z < 92) which were not found and therefore identified as still undiscovered, corresponding to atomic numbers 43, 61, 72, 75, 85, 87 and 91.
ðɛɹwˌɜː sˈɛvən ˈɛlɪmənts wɪð zˈiː nˈaɪnti tˈuː wˌɪtʃ wɜː nˌɑːt fˈaʊnd ænd ðˈɛɹfoːɹ aɪdˈɛntᵻfˌaɪd æz stˈɪl ʌndɪskˈʌvɚd, kˌɔːɹɪspˈɑːndɪŋ tʊ ɐtˈɑːmɪk nˈʌmbɚz fˈoːɹɾi θɹˈiː, sˈɪksti wˈʌn, sˈɛvənti tˈuː, sˈɛvənti fˈaɪv, ˈeɪɾi fˈaɪv, ˈeɪɾi sˈɛvən ænd nˈaɪnti wˈʌn.