The various indicators and strategy discussed in this issue by Sylvain Vervoort in "The Quest For Reliable Crossovers" is available for download here.
Once downloaded, from within the NinjaTrader Control Center window, select the menu File > Utilities > Import NinjaScript and select the downloaded file. This indicator is for NinjaTrader Version 6.5 or greater.
You can review the indicator's source code by selecting the menu Tools > Edit NinjaScript > Indicator from within the NinjaTrader Control Center window and selecting ZeroLagEma, ZeroLagHATEM, ZeroLagTEMA.
You can review the strategy source code by selecting the menu Tools > Edit NinjaScript > Strategy from within the NinjaTrader Control Center window and selecting VervoortMACrossOver.