Johanson : Balun filter is optimized for 868 MHz SRD band - EDN
Balun Transformers - STMicro | Mouser
Figure 1 from Balun bandpass filter with wide upper stopband using silicon-based integrated passive device technology | Semantic Scholar
Understanding the RF Balun Transformative Function | DigiKey
CC2642R: Using a Johanson balun-filter for RF - Bluetooth forum - Bluetooth®︎ - TI E2E support forums
Baluns - STMicroelectronics
Wideband balun filter on slot‐line resonator with intrinsic balanced performance in magnitude and phase - Feng - 2019 - International Journal of RF and Microwave Computer-Aided Engineering - Wiley Online Library