The claim describes standard linguistic processes of phonological evolution; while specific historical pathways are studied empirically, the core definitions are established linguistic common knowledge.
The claim states that phonological evolution involves regular processes of phoneme elision, vowel nasalization, and tonogenesis. These are foundational, textbook concepts in historical linguistics and phonology describing how sound systems change over time. While individual mechanisms like tonogenesis or nasalization are studied empirically (as seen in papers 8 and 9), the broad statement that phonological evolution involves these processes is a matter of established linguistic knowledge. Therefore, the verdict is COMMON_KNOWLEDGE, with supportive papers illustrating specific instances of these evolutionary phenomena.