References – SN 22.95: A Lump of Foam 
Readings by Ajahn Karuṇadhammo: [Aggregates]
Sutta: SN 22.102, Khandhasaṁyutta, “Perception of Impermanence.”
Sutta: SN 22.95, Khandhasaṁyutta, “A Lump of Foam.”
Sutta: SN 22.33, Khandhasaṁyutta, “Not Yours (1).”
The Fourth Foundation of Mindfulness [2013], Session 31
“Is there a special meaning for which simile is compared to which khandha in SN 22.95?” Answered by Ajahn Karuṇadhammo. [Similes] [Aggregates] // [Impermanence] [Body/form] [Feeling] [Perception] [Volitional formations] [Consciousness]
The Fourth Foundation of Mindfulness [2013], Session 31, Excerpt 3