## 1 Introduction
The third-order oscillator in Figure 3 of Reference [26] uses three voltage controlled differential voltage current conveyors (VC-DVCCs) and three grounded capacitors. The third-order oscillator in Reference [27] uses three MO-CCCIIs and three grounded capacitors. The third-order oscillator in Reference [28] uses three multiple-output current differencing transconductance amplifiers (MO-CDTAs) and three grounded capacitors. Although the third-order oscillator in Reference [29] uses two multiple-output second-generation current conveyors (MO-CCIIs), three resistors, and three grounded capacitors, one of the resistors is a floating connection. The third-order oscillator in Reference [30] uses three multiple-output differential voltage current conveyors (MO-DVCCs), three resistors, and three grounded capacitors; however, one of the resistors is also a floating connection. The oscillator in Figure 2 of Reference [31] uses three operational transresistance amplifiers (OTRAs), four resistors and three capacitors; however, not all of the resistors and capacitors are grounded. In 2015, two new third-order quadrature oscillators were proposed [32], which employed two multiple-output differential voltage current conveyor transconductance amplifiers (MO-DVCCTAs), one/two resistors, and three grounded capacitors. However, these circuits [22; 23; 24; 25; 26; 27; 28; 29; 30; 31]; more of the following drawbacks: (i) the inclusion of three/four active components [22; 23; 24; 26; 27; 28; 30; 31]; (ii) the lack of both a voltage-mode and current-mode quadrature oscillator in one circuit topology [22; 23; 24; 25; 31]; (iii) the lack of a resistorless oscillator [24; 29; 30; 31; 32]; (iv) the lack of an independently electronically tunable for the oscillation condition and frequency [22; 24; 30; 32]; (v) the lack of amplitude-controllable for output current signal [22; 23; 24; 30; 31; 32]; and (vi) the lack of quadrature voltage outputs, quadrature current outputs, and a high-impedance amplitude-controllable current output in one circuit topology [22; 23; 24; 30; 31; 32], especially, the electronically controllable amplitude of the sinusoidal current output signal that can be easily used in AM/ASK systems. In this paper, a new approach to realize third-order quadrature oscillators using a lossy integrator and two lossless integrators is proposed. The proposed third-order quadrature resistorless oscillator employs two MO-CCCATAs and three grounded capacitors. The proposed third-order quadrature oscillator has the following seven advantages simultaneously: (i) it contains only two active components and three grounded capacitors; (ii) it has both voltage-mode and current-mode third-order sinusoidal quadrature oscillator in the same topology; (iii) it achieves quadrature voltage outputs, quadrature current outputs, and a high-impedance amplitude-controllable current output in one circuit topology; (iv) it has independent electronically tunable characteristics for the condition of oscillation (CO) and the frequency of oscillation (FO); (v) it provides a high-impedance current output of adjustable magnitude, without effecting the CO and FO and is suitable for AM/ASK modulations; (vi) it uses only grounded capacitors; and (vii) it holds low active and passive sensitivity performances. Tables 1 and 2 compare the main features of the proposed circuit with previous third-order sinusoidal oscillators [22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32].