Used for

• Delay equations (Differential equations)
• Delay functional differential equations
• Differential delay equations
• Differential equations with lag
• Differential equations--Delay equations
• Differential equations--Retarded argument
• Differential equations--Time-lag equations
• Functional differential equations--Delay equations
• Retarded argument (Differential equations)
• Retarded differential equations
• Retarded functional differential equations
• Time-lag systems (Differential equations)