SOLVED: Problem compiling code error: "undefined Reference to 'Timer1'"

Projects Programming
2 
#include <Arduino.h>
#include <PinChangeInt.h>
#include <TimerOne.h>
...

void RISING_ISR()
{
    Timer1.start();
}   //End RISING_ISR()

void FALLING_ISR()
{
    Timer1.stop(); //Stop Timer1
    RC_Ch[State].RecVal = TCNT1;
    ++D_State;
}  // End FALLING_ISR()

void FINISHED_ISR()
{
    Timer1.stop();  //stop Timer1
    ++O_State;
}  //FINISHED_ISR()

Error Logs:

RC_Channel_Mod.cpp.o: In function `FINISHED_ISR()':
C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:131: undefined reference to `Timer1'
C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:131: undefined reference to `Timer1'
RC_Channel_Mod.cpp.o: In function `FALLING_ISR()':
C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:124: undefined reference to `Timer1'
C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:124: undefined reference to `Timer1'
RC_Channel_Mod.cpp.o: In function `Transition()':
C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:251: undefined reference to `Timer1'
RC_Channel_Mod.cpp.o:C:\Users\Angela\AppData\Local\Temp\build423434619881223618.tmp/RC_Channel_Mod.cpp:251: more undefined references to `Timer1' follow