Undefined Character (U+0381)

Block:	Greek and Coptic, U+0370 - U+03FF^[1]
Plane:	Basic Multilingual Plane, U+0000 - U+FFFF^[1]
HTML Entity:	`΁` `΁`
UTF-8 Encoding:	`0xCE 0x81`
UTF-16 Encoding:	`0x0381`
UTF-32 Encoding:	`0x00000381`

References