-d3_intro.html:
updated:
    https://github.com/d3/d3/wiki => https://d3js.org/what-is-d3


-d3_selection.html: link update:
unpdated:
    https://github.com/d3/d3/blob/main/API.md#selections-d3-selection => https://d3js.org/d3-selection
    https://github.com/d3/d3-selection/blob/v3.0.0/README.md#selection_attr => https://d3js.org/d3-selection/modifying#selection_attr
    https://github.com/d3/d3-selection/blob/v3.0.0/README.md#selection_style => https://d3js.org/d3-selection/modifying#selection_style
 

-d3_loading_data.html: 
updated:    
    https://github.com/d3/d3-fetch => https://d3js.org/d3-fetch

-d3_scales.html:
updated: 
    "https://github.com/d3/d3-scale/blob/main/README.md#schemeCategory10" (removed) 
    "https://github.com/d3/d3/blob/main/API.md#scales-d3-scale => https://d3js.org/d3-scale


-d3_min_max.html:
updated:
    https://github.com/d3/d3-array/blob/main/README.md#statistics => https://d3js.org/d3-array/summarize#summarizing-data


-d3_axis.html:
updated:
    https://github.com/d3/d3/blob/main/API.md#axes-d3-axis (removed)
    https://github.com/d3/d3-axis => https://d3js.org/d3-axis

old: (same lines appeared in d3_groups_and_transformations.html & d3_interaction.html & d3_brushing.html)
    /* AXIS */
    let axisX = d3.axisBottom() //define an axis on the bottom

    axisX.scale(scaleX) //bind the axis to the scale
new:
    /* AXIS */
    let axisX = d3.axisBottom(scaleX) //Constructs a new bottom-oriented axis generator for the given scale


-d3_interaction.html:
updated:
    https://github.com/d3/d3-selection/blob/main/README.md#handling-events => https://d3js.org/d3-selection/events


-d3_brushing.html
updated:
    https://github.com/d3/d3/blob/main/API.md#brushes-d3-brush => https://d3js.org/d3-brush


-d3_transitions.html
updated:
    https://github.com/d3/d3-transition => https://d3js.org/d3-transition
    https://github.com/d3/d3-ease/blob/v3.0.1/README.md#_ease => https://d3js.org/d3-ease
    

-d3_line.html
updated:
    https://github.com/d3/d3/blob/main/API.md#lines => https://d3js.org/d3-shape/line#_line

old:
        diagram.append("g")
           .append("path")
           .data(dataByChild)
           .style("stroke", "steelblue")
           .attr("d", d => {
             return line(d[1]);
           })
           .attr("fill", "none")

        let axisX = d3.axisBottom() //define an axis on the bottom

        axisX.scale(scaleX)
           .ticks(5)
           .tickFormat((d, i) => d.toString());

new:
        /* PLOT DATA */
        diagram.append("g")
          .selectAll()
          .data(dataByChild)
          .join("path")
          .attr("d", d => line(d[1]))
          .style("stroke", "steelblue")
          .attr("fill", "none")
        
        let axisX = d3.axisBottom(scaleX) //define an axis on the bottom

        axisX.ticks(5).tickFormat(d => d.toString());


-d3_map.html:
updated:   
    https://github.com/d3/d3-geo/blob/v3.0.1/README.md#geoAzimuthalEqualArea => https://d3js.org/d3-geo/projection

        

-d3_more.html:
updated:
    https://github.com/d3/d3-zoom/blob/v3.0.0/README.md#zoom => https://d3js.org/d3-zoom
    https://github.com/d3/d3/blob/main/API.md#geographies-d3-geo => https://d3js.org/d3-geo
    https://github.com/d3/d3/blob/main/API.md#paths-d3-path => https://d3js.org/d3-path, https://d3js.org/d3-polygon, https://d3js.org/d3-quadtree
    https://github.com/d3/d3/blob/main/API.md#shapes-d3-shape => https://d3js.org/d3-shape#d3-shape 
