Integrable nonlinear Klein–Gordon systems with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="d1e85" altimg="si7.svg"><mml:mi mathvariant="script">PT</mml:mi></mml:math> nonlocality and/or space–time exchange nonlocality

In additional to the parity ($\mathcal{P}$) symmetric, time reversal ($\mathcal{T}$) and $\mathcal{PT}$ symmetric nonlocal integrable systems, some other types of Klein-Gordon models with space-time exchange nonlocality moving nolocality are proposed. The Lax pairs established nonlinear equations explicitly given. A special soliton solution, composed $\mathcal{PT}$-symmetric part $\mathcal{PT}$-antisymmetric part, is illustrated shape change.